Compurers Educ. Vol. 18, No. l-3, pp. 155-162, 1992 Printed in Great Britain

0360-1315/92 $5.00 + 0.00 Pergamon Press plc

BLOCKS TO THE EFFECTIVE USE OF INFORMATION TECHNOLOGY IN HIGHER EDUCATION

NICK HAMMOND,’ NIGEL GARDNER,~ SIMON HEATH,~ MICHAEL KIBBY,~

TERRY MAYES,’ RAY MCALEESE,’ CHRISTINE MULLING~ and ANNIE TRAPP’

‘CT1 Centre for Psychology, University of York, Heslington, York YOl 5DD, ‘Programme on Information and Communication Technology, University of Oxford, Oxford, ‘CT1 Centre for Land Use Studies, University of Aberdeen, Aberdeen AB9 lFX, 4Centre for Academic Practice, Strathclyde University, Glasgow Gl IQE, ‘Institute for Computer-Based Learning, Heriot-Watt University,

Edinburgh EHl IHX and ‘CT1 Centre for Textual Studies, University of Oxford, Oxford, U.K.

Abstract-This paper reports on the outcome of a seminar addressing issues in the exploitation of IT in teaching within Universities in the U.K. The seminar brought together experts with a range of experience in the use of educational technology, and focused on educational and organisational issues rather than on technical ones. Three surveys of the views of University lecturers on the use of computers in teaching, and the associated problems, are reported, followed by discussion of educational and organisational routes to lowering some of the existing barriers to more effective applications of educational technology.

INTRODUCTION

Why are computers so little used for teaching in the U.K. university sector? And why is what use

there is almost entirely limited to tool-based applications? Why is it so rare for CAL to be integrated into the curriculum? Certainly microcomputers are starting to become widely available to teachers and students, and there is increasing information on available software and courseware within disciplines. For instance the Computers in Teaching Initiative (CTI) supports a vigorous programme informing lecturers of the availability of computer-based teaching materials and the opportunities they offer (see[l] for further information on the Initiative). Despite coordinated efforts such as these to promote the effective use of computers in teaching, the uptake is not as high as many have hoped.

The reasons for this are many: some no doubt reflect the quality and nature of the available materials, and others concern the educational context in which the technology is to be used. The instructional goals embedded within a piece of courseware all too often fail to match the goals of the course it purports to support. Yet other reasons may concern the organisational and political context: institutions and departments, whether by intent or default, may give little assistance to those wishing to exploit innovative approaches. Indeed, some argue that the key factors required to develop educational computing in universities are organisational, and advocate a strategic approach through centralised but cooperative management [2]. Certainly models of the adoption of computing into the university cur- riculum based solely on characteristics of individual lecturers tend to have little predictive value [3].

This paper results from a seminar convened to explore these educational and organis- ational barriers to the effective exploitation of computers in teaching, and to consider possible solutions. The seminar brought together two groups of experts, the first drawn from the staff of CT1 Centres with particular knowledge of the problems of users-teachers and learners-and the second drawn from educationalists. The contributors were provided with a list of questions, intended to serve three roles: to define the scope of the seminar, to give a con- text within which the individual contributions could be viewed, and to help define issues for further research and clarification. The questions are shown in Fig. 1. The extent to which these questions were addressed was obviously limited, but they nevertheless provide a structure for this paper.

155

156 NICK HAMMOND rt al.

--...-__~ .~ ~ __....-. 1. DEFINING THE PROBLEM

1 1 What IS Ihe current take-up and pattern of use of computers-based learning In higher education? Is take-up commensurate wtth Ihe avaIlable resources and quality of soflware/courseware, or IS there evtdence for additlonal blocks?

1.2 What are the perceived barrrers and incentives to the use of CBL in /HE? How are such findrngs to be tnterpreted7

1 3 How wet1 or poorly is CBL integrated into ed~~catlonal practice tn HE, and why7

1 4 What are the key features of the organisattonal (and pollizcal) context which contribute t( the problem?

2. TOWARDS SOLUTIONS

2 1 What suggestlons for change (technical, educatlonal, organlsatlonal) result from surveys of usage and barriers lo use7

2.2 What opportunltles could new technology or approaches (whether In software developmenr or In use) bnng lo help overcome blocks in the use of Cf3L in HE.

2 3 What changes in educatjonai practtce might help7

7 4 What changes in organJsalional poltcy or structure would be most effective in OvercomIng barriers??

2.5 How should change best be tnstlgated (at the techmcal. educational and organisalfonal levels)? What policy IS adopted by extstmg groups?

2.6 What can be learned from the sltuatlon elsewhere (other sectors of education and overseas)?

Fig. I. Questions on the use of information technology in education provided to contributors to the seminar.

SURVEYS OF LECTURERS’ VIEWS

A number of authors have identified characteristic barriers to the uptake of educational technology, for example[4]. Factors cited include the shortage of lecturers time, poor rewards for teaching innovation or courseware development and the “not-invented-here” syndrome[5]. How- ever, we have found no published reports of systematic surveys within this area to substantiate these claims, and so the work reported below is of particular interest despite the inevitable methodologi- cal problems with surveys of this sort.

The CT1 Centres, from which the first group of experts in the seminar were drawn, are in a unique position to report on current practice and problems. The Centres are responsible for promoting computer-supported learning within their particular disciplines, and there is no other comparable body which combines subject expertise, educational and technical know-how and wide access to the views and activities of university teachers. Summary findings from surveys conducted by three CT1 Centres are presented below. The surveys reflect on the state of current practice (questions 1 .l and 1.3 in Fig. I) and the perceived incentives and barriers to computer use in teaching (questions 1.2 and I .4).

Questionnaire surz’ey’s on blocks to computer use

Reasons for the slow adoption of CAL by university lecturers has been investigated in two surveys by the CT1 Centre for Land Use Studies. The first survey addresses academic staff within the Centre’s discipline area throughout the U.K. and the second focuses on one campus-the University of Aberdeen-but encompasses lecturers from all subject areas. Some key results are presented in Fig. 2 (national survey of discipline-specific staff) and Fig. 3 (survey of Aberdeen staff).

For the first survey, respondents were asked “what factors inhibit you in the use of computers in your teaching?” and to tick the three most important of nine factors described in the questionnaire (see Fig. 2 for details). Respondents were also invited to specify additiona factors. In the second survey, respondents were asked to rate the importance of nine factors on a scale of I (very important) to 4 (very unimportant).

Lack of time

Financial constraints

Lack of training

z Lack of support staff .2? z .t

Info on software

? 2 Info on potential

Perceived benefit

Student access

Software quality

Blocks to the effective use of IT

0 10 20 30 40 50 60 70 80

Percent of respondents choosing factor

157

Fig. 2. Percentages of respondents indicating factors perceived to inhibit use of computers in teaching. The nine factors were: staff perceive benefits but have insufficient time to investigate or develop teaching software; financial constraints; lack of staff training; lack of support staff to assist lecturers in the use of computers; lack of information on suitable software for use in teaching; not enough information on the potential of computers as an aid to learning; staff do not perceive benefit from the use of computers in teaching; insufficient access for students to the computer hardware; poor quality of available software.

The predominant finding from both surveys is that staff perceive lack of time (whether for modifying courses, evaluating courseware or developing materials themselves) as a major barrier. Also high on the list of priorities are lack of support staff, lack of training and lack of information on suitable materials. It is interesting that factors such as lack of student access to hardware and quality of software are not considered to be such strong blocks to computer use. These findings accord with the view that significant improvements could be brought about by changes in organisational policy: for lecturers to find time implies in part a change in institutional priorities through policies, support structures and rewards, and in part a reduction in the size of perceived barriers. Perceived barriers to the adoption of CAL can be lowered through better information, staff training and the provision of appropriate development tools. Both institutional structures and national structures are likely to be necessary to achieve this.

Time to develop courseware

Support staff

5 Time to evaluate z .g @ Suitable courseware s ‘J

$ Classroom supervision

Staff traming

Encouragement

0 10 20 30 40 50 60 70 80 90

Percent of respondents rating factor as important

Fig. 3. Percentages of respondents rating each factor as important or very important. The factors were: lack of time to develop CBL courseware; lack of support staff for software development and maintenance; lack of time to evaluate the potential of computers in teaching and to remodel the course to incorporate existing CBL courseware; lack of suitable CBL courseware; lack of staff for supervision of students in the use of CBL courseware during formal or ad hoc class time and lack of suitably equipped classrooms; lack of staff training in the application of computers in teaching; lack of encouragement for integration

of CBL in your courses and recognition in promotion assessment.

158 NICK HAMMOND et al

Questionnaire survey of problems and bene$ts in the use of computers,for teaching humanities

In 1990, a national survey of all humanities departments in universities, polytechnics and colleges of higher education was conducted by postal questionnaire. The aim was to discover the current level and nature of the use of computers in teaching and research in the humanities community in the U.K. The questionnaires were sent to heads of department, and about half were completed by a person of this status, and thus were likely to reflect their viewpoint. Questions addressed such issues as availability of computing resources in departments; whether formal courses on computer use were offered (learning about computers); the use of computers to teach specific parts of the curriculum (learning with computers) and the reasons for introducing a computing element into courses. Effects on departments were explored, and in particular the perceived benefits and problems experienced.

More people perceived benefits from the introduction of computing than experienced problems with its use. Benefits related mainly to staff interests, and particularly to improved IT skills among staff, increased research productivity and saving time (all scoring over 70%). Use in teaching and perceived benefits to students were much further down the response scale. Since the questionnaire was addressed to staff this is perhaps hardly surprising.

The most prominent problems reported were associated with costs and staffing. Many respon- dents quoted “lack of money, lack of space and lack of time”. Cost problems included both initial capital funding and the ability to upgrade and expand equipment. There was considerable feeling that low priority was given to humanities or arts computing needs. Staffing problems concentrated on lack of staff experience and skills in the field of IT; lack of time for picking up such skills, for setting up or maintaining equipment and for producing software or for teaching with computers. Inertia was seen as more of a problem than staff or student resistance as such. Lack of information relating to use of IT did not figure highly as a problem.

When problems and benefits were examined by discipline, there was a marked tendency for those experiencing the most benefits to also experience the most problems, and in re- verse, those experiencing the fewest benefits also experienced the least problems. This trend seemed to be dependent on amount of resources available, amount of instruction (to both students and staff) and actual use in teaching. Although it might seem an obvious point, it appears that it is only through increased familiarity leading to increased use that both benefits and problems are recognised. It seems to be an evolving situation, where once resources are made available they are used firstly to enhance staff interests and then filter down to use with students. To encourage the spread of computer use to enhance teaching and learning in the humanities, a good place to start would be with a better overall IT strategy, particularly addressing the political and organisational issues of improved funding, especially for undergraduate facilities, and to enable staff to acquire the necessary skills and

experience.

Interview survey of attitudes to computer-based teaching

The third survey to be reported employed a different methodological approach. When visiting psychology departments to give presentations, the CT1 Centre for Psychology conducts semi-struc- tured interviews with teaching staff. Prior to a visit, a number of both users and non-users of computer-based teaching are identified and appointments arranged. The interviews last about 30 min and generally occur prior to any presentations or demonstrations by the CT1 Centre. The purpose of the interview is to find out how the lecturer currently uses computers, their knowledge of computer-based resources and their attitudes towards computer-based teaching. The key findings are summarised below.

The first part of the interview concentrates on actual usage of computers in teaching. Lecturers responsible for teaching statistics or running laboratory practicals are more likely to use software packages than other lecturers. This confirms the finding of a previous questionnaire that virtually all departments use computer facilities for teaching statistics and practical classes[6]. Few lecturers report using simulations, demonstrations, self-testing materials or structuring tools (such as

concept mapping[7]) within their teaching. It is also rare for computers to be used to support innovative methods of presentation or teaching methods. For example, liquid crystal display units

Blocks to the effective use of IT 159

are not widely used and, with some notable exceptions, there is little use of electronic communi- cation with students.

The interviews also suggest that lecturers tend to call on tools they already use for their research for teaching purposes. For example, word processing packages are used to prepare course notes, reading lists; data analysis packages are used to analyse class practical results; and in some cases a specific software package is used for both research and teaching. This has implications for the purchasing policy within departments. An ud hoc policy all too often results in a research culture based on workstations and Apple Macintosh hardware and a teaching culture based on PC hardware, to the detriment of teaching innovation.

The second part of the interview was concerned with attitudes to the use of computers in teaching. When asked what the main motivating factor would be to introduce computer-based teaching into their own course, the most frequently cited reason given by lecturers was the availability of good software. In some cases this reflected a lack of knowledge of existing software. Others claimed that their courses would not be improved by computer-based teaching methods. When asked to describe three ways in which computers might be potentially used on their course, the comments revealed a narrow view of how software could be used for different purposes and of the potential for introducing innovative teaching methods.

The majority of lecturers interviewed showed a positive attitude to computer-based teaching in general but were less enthusiastic about its relevance on their own course. They generally perceived their department’s attitude as positive, even if not matched by resourcing, but were less clear about the attitude of their organisation. Indeed, no-one reported being under any pressure either from their peers, department or organisation to introduce CAL into their courses. Lecturers considered making radical changes to their course a low priority and expensive in terms of time and reward. In most departments, lecturers could receive some technical support but no training or guidance in preparing or utilising computer-based materials.

Discussion

The three surveys provide some insight into the questions listed under Defining the Problem in Fig. 1. They confirm previous reports that computer use in teaching is predominantly tool-based, with little use of tutorial, demonstration or other teaching-support software. Failure to develop these latter uses may result in part from lack of available products, but it stems also from ignorance of what is available and how software might be used in innovative ways. Advice on these matters within institutions seems virtually non-existent. However, the main perceived blocks are lack of time (and, by implication, a low priority on the part of individuals and organisations), lack of resources (particularly in non-science areas) and lack of support and training. In view of the suggestion that those with most experience were also aware of the most problems, it would be interesting to know how the perception of blocks to IT use in teaching changes with practical experience. It is likely that some of the respondents were hypothesising from a state of blissful ignorance.

Turning to the organisational context, it is clear that few institutions explicitly reward teaching innovation. It is of particular interest that, despite recent political rumblings on teaching quality, few lecturers perceived any pressures from their department or institution to introduce innovative approaches to their courses. The surveys help identify a number of routes for bringing about change, whether through the better provision of information, through the design of more suitable software tools or through organisational means. The next section explores some of the issues behind such changes.

EDUCATIONAL AND ORGANISATIONAL ISSUES

The second group of experts at the seminar on which this paper is based is drawn from those with experience of promoting educational and organisational change. We make no attempt to cover the full range of issues and possible strategies for solutions; rather the participants provided some snapshots of particular directions that might be taken. The following section suggests a direction for the development and use of courseware materials and tools, while the final section discusses background issues to institutional support for computer-based learning.

160 NICK HAMMOND et al.

Towards educationally-efective courseware

One route to solving the problem lies in the provision of more appropriate courseware and software tools. Certainly some progress has been made in increasing available information through the provision of catalogues of computer-based teaching material by the subject-specific CT1 Centres. However, the use of existing software is widely recognised to fall far short of what is thought to be desirable. It is difficult to make unqualified statements about the use of computers because, as Lewis[8] points out, very little evaluation of the use and usage of IT to support higher

education has been performed. Those who use such phrases as the ‘not-invented-here syndrome” are underestimating and

undervaluing the conventional process by which lecturers prepare and update their materials. They refer to textbooks, monographs, the research literature, and their own research and experience for sources of factual material, ideas, representations, and organisation during the preparation of lecture notes, seminars and tutorials. What emerges is that lecturer’s interpretation of the topic to be taught. Computer-based materials are quite justifiably approached in the same manner when being considered for inclusion in a lecturer’s course materials. However, most courseware is not amenable to the same process of seamless incorporation into the body of a lecturer’s course materials, but must be used as it stands or be rejected. Too often the latter option is taken.

Designing an environment in which existing courseware may be re-used in various applications has been addressed during the recently completed exploratory phase of the EC DELTA programme because of its fundamental importance to the economic and practical viability of much effort put into the creation of courseware. In the SAFE project (Dl014), the concept of half-fabricates is developed, which recognises that various tools may operate at various stages during the construction of learning material, so that the output of one tool is the input to the next [9]. An alternative model for reusability, which emerged from consideration of the structure of hypermedia data elements in the same project, is that all items of a hypermedia database should have the same data structure, whatever the medium of the content or the modality by which they are presented to the learner. This allows a set of common database tools for structuring the database, although the multimedia content of each item in the database clearly requires medium-specific editors[lO].

The latter representation of re-usability has significance not only at the stage of authoring hypermedia courseware, but also for all its other users, who may tailor the original, probably very large, database as a resource base of learning material in a particular subject area. Such users may be courseware developers, who may structure or restructure parts of the database for commercial reasons, teachers who may modify it for the pedagogical reasons indicated above, and learners who

may edit or supplement the database as part of the learning process[l I]. While hypermedia is being widely considered as a means of generating and delivering

computer-based teaching because of its interactivity and exploratory mode of use[l2], its potential for supporting re-usability on a large scale may in the final outcome be the prime factor in its wide adoption in learning.

Towards institutional support for computer-based learning

Conkin[l3], in his 1987 review of hypertext, asks why it took over 20 years before the early pioneering demonstrations of the hypertext idea were taken out of the research and development laboratory and implemented in real working contexts. It is usually assumed that it took this long because the idea needed the available technology to become powerful enough to implement it in a usable and effective way. More importantly, Conklin argues, the idea itself took a long time to be fully appreciated. Thus, the very idea of the computer as a cognitive tool, as an augmenter of individual human intelligent performance, was a concept that required a long gestation period. It may be that this represents a necessary process, and we are seeing the same slowly-dawning realisation about CAL by the mainstream world of education. Perhaps the main blocks to implementation of CAL on a worthwhile scale lie in the fact that we have not yet put the idea across properly. On the other hand, we may be guilty of selling the wrong idea. To expect the educational system to go from a world almost totally without technology, except where teaching people how to use the technology is the point of the exercise, to a world where most learning occurs from a computer screen, is too big a jump. Just as with hypertext, the idea that the computer can be a

Blocks to the effective use of IT 161

tool to help students learn, not so much by acting as a multimedia delivery mechanism for knowledge, but by augmenting the learner’s ability to ask questions, to explore, to form active strategies and so forth, is an idea that is so obvious that we (the converts) do not even bother to spell it out. Yet the full implementation of this idea would have the most radical consequences for higher education. It would mean that we would be accepting responsibility for shaping the learning process. This is not something that Universities have previously been anxious to do. In fact, to do so would require a reappraisal of priorities because what is being offered is not a technological “fix” to make higher education more cost effective, but a requirement to take seriously something that has previously only received lip-service, that is learning itself.

Universities are places that the outside world looks to for expertise, yet they are notoriously weak in applying advanced knowledge to their own organisation and procedures. To take a random example, there are occupational psychologists in most U.K. Universities who advise industry on selection procedures, Yet this expertise is almost totally ignored in the University’s own selection procedures. It is much the same with teaching. University teachers, as we all know, are neither professionally trained, nor properly recognised, by their own institutions as teachers. The point is that Universities do not know how to implement new technology in their own service, even if it has been developed by its own researchers. Even if they did know how to do this, the innovative implementation of technology for teaching would not solve the problem that policy makers want to solve, which is how to teach ever-increasing numbers of students with almost no increase in resources. It might ultimately be possible to use CAL to achieve real gains in learning with less contact with teachers, but to get to this point will require a considerable investment of both resources and attention to the learning process.

Part of the problem lies in the confusion between research and development. We are equipped to pursue the former but not the latter. Yet most of the real problems in this area are not problems of research per se. Of course many research problems remain, but the most challenging aspects are those of creating large-scale change. We must build and demonstrate systems that are effective learning environments, but we must also test their effectiveness in the context of real implemen- tation, that is in real pedagogical experiments on a large scale (with appropriate safeguards for individual students). As researchers, we must raise the profile of evaluation and make sure that the same ingenuity goes into evaluation as into the design of the instructional software.

Principal Alistair MacFarlane, who has been responsible for setting up Heriot-Watt University’s Institute for CBL, has said that Universities should be involved in the large-scale development of this technology, but that they cannot do it alone. The intensely supportive learning environments on which Universities will concentrate a few years hence cannot be produced, at present, by the efforts of the staff from the institution itself. On the contrary, the development process will need to be a collaboration with equipment manufacturers, software producers, and possibly publishers. It is unlikely that we can succeed without such collaboration, while it is also the case that such development could not occur without us.

CONCLUSIONS

The seminar sought clarification of the issues raised by the question listed in Fig. 1. In this it proved partially successful. The first section of the paper, summarising findings from three surveys of lecturers’ views and practices, revealed a pattern of IT use and perceived barriers to its use compatible with a general lack of institutional concern and support for computer-based learning. The surveys also pointed towards potential routes for change, but the overall low level of innovative use of IT for teaching means that what evidence does exist on the strengths and weaknesses of specific approaches is eclipsed by wider concern for the more general barriers to its use. So while some of the solutions proposed in this paper may well meet requirements of lecturers, the surveys provide no further insight into such solutions as they are currently so rare. The second section, concerned with educational and organisational issues, discussed some directions for courseware development and for institutional support.

There is a great danger that support for the use of technology focuses on the technology rather than on the use. Whilst it is clearly important to provide the infrastructure support, the technical backup and information on what is available, this is only the starting point, the enabling condition,

162 NICK HAMMOND et (11.

for what follows. This point was made by contributors to the seminar particularly in relation to the development of CBL support in universities in the U.S.A. Educational technology, once we move away from computers as mere replacements of existing tools, inevitably raises questions about its optimal use for the learning within the particular educational and institutional context. As argued in the preceding section effective use of computer-based learning requires a reappraisal of how learning should take place within universities.

It is too often the sole responsibility of the lecturer not only to identify courseware or software, but to devise a sound educational strategy for its use, to negotiate suitable resourcing and to fight the organisational inertia in the practicalities of carrying through an innovative teaching project. On the whole, U.K. lecturers receive no formal training in educational theory and practice, though one hopes they have picked up the requisite skills for conventional teaching methods. To move beyond the familiar boundaries requires an uncomfortable questioning of one’s presuppositions. Venturing into unknown territory also incurs risks of failure or institutional disapprobation. The finding that perception of benefits and of problems go hand in hand suggests that use of educational technology may well lead to a questioning of educational methods: espousing educational technology seems inevitably to lead us down a road of educational change. If this view is accepted, then the implementation of educational technology should be the responsibility of not just the technologist: psychologists concerned with cognitive change, educationalists concerned with educational change and policy-makers concerned with organisational change all have distinctive and important roles to play. Computer-based learning is about education, not computers.

1. 2.

3.

4. 5.

6.

7. 8.

9.

IO.

11.

12.

13.

REFERENCES

Darby J.. The computers in teaching initiative. A progress report. CTISS File 10, 3 5 (1990). Bidin A. R. H. and Drabble G., An organizational approach towards the development of educational computing in a university environment. Cwnpnpurers Educ. 14, I37 I43 (1990). Mudd S. and McGrath K., Correlates of the adoption of curriculum-integrated computmg in higher education. Computrr.s Educ. 12, 457 463 (1988). Darby J., Computer literacy or computers in teaching’? CTISS File Il. 48 49 (1991). Gardner N. and Darby J.. Using computers in university teaching: a perspective on key issues. C‘onzpurcrs Educ. 15, 27-32 (1990). Hammond N. V. and Trapp A. L.. Computers in psychology teaching in the U.K. Belwr. Rrs. Met/~. Imrrum. C‘omputer.~ 23, II8 120 (1991). Trapp A. L. and Hammond N. V., Concept mapping tools: a different approach. ~,~#rol. Sgftrt,. New.~ 2, IO I I (1991). Lewis R., Computers in higher education teaching and learning: some aspects of research and development. CTlsS Fik 11, 3-7 (1991). Derks M.. Bulthuis W., Monaghan P., Keane M., Easterbrook M., Nienhuis E. and Bloemberg W.. Learning material development. tools. and environments. DELTA SAFE project (DlOl4) Report OS-ID/l. Philips. Eindhoven (1989). Hatzopoulos M., Dimopoulou K.. Gouscos D.. Spiliopoulou M., Vassilakis C. and Vazirgiannis M.. DELTA SAFE project (DlOl4) Report HYP!20 Final Report on hypermedia databases. Philips, Eindhoven (1991). Kibby M. R., Tanner G., Mayes J. T.. Knussen C. and Grant S.. DELTA SAFE project (Dl014) Report HYP.21 Final Report on user interfaces for hypermedia. Philips, Eindhoven (1991). Jonassen D. H. and Grabinger R. S.. Problems and issues in designing hypertext/hypermedia for learnmg. In Designing H~prrre.ul!H_~~permedirr.fhr Lrcrming (Edited by Jonassen D. H. and Mandl H.). pp. 3-25. Springer. Heidelburg (1990). Conklin J.. A survey of hypertext. MCC Technical Report, No. STP-356 X6. Rev. 2 (1987).