Everybody who enjoys the calming sound of turning book pages most probably dislikes the thought of having to do with a computer mouseclick instead. Today's technology is advanced, but not yet advanced enough for most of us to really want to read electronic books. The general market seems to reflect this, since it has not developed as steadily as it was predicted only a few years ago. The 1996 Frankfurt Book Fair, one of the world's largest international book fairs, saw a smaller percentage of multimedia products than anticipated (Baier, 1996). Klaus-Dieter Lehmann, Director of the Deutsche Bibliothek stated in an interview that only 2,000 to 3,000 out of 300,000 new acquisitions per year are digital, everything else still is on paper (Lehmann, 1996).
Electronic books do have some advantages though. They allow users to quickly locate specific information through built-in search functions, and information can be updated and kept accurate easily. Electronic format therefore is a valid alternative to print media, especially with regard to directories, dictionaries, encyclopedias, and reference works.
In astronomy, extensive use of the capabilities of e-books has been
made in regard to user manuals for telescopes or individual
instruments. These days the latest information often can only be found on
the Web. For conference announcements and programs, it has become standard
for users to obtain
up-to-date information from a Web page. Likewise, more and more conference
proceedings
can be found on the Internet (e.g., ``Weaving the
Astronomy Web (WAW)''
, ``Library
and Information Services in
Astronomy II (LISA II)'' or the ``Astronomical Data
Analysis Software and Systems (ADASS)'' conference
proceedings).
A novelty in astronomy was the book ``Information &
on-line data in astronomy'' (Egret and Albrecht, 1995); in
addition to the paper version, an electronic complement is maintained
on the World Wide Web, from where chapter abstracts are
available. Hypertext links mentioned in the book are provided as
clickable links.
On the other hand, electronic books and documents have specific disadvantages. With regard to networked documents, version control poses a distinct problem. We are used to informing our users about the edition of a book or the publication year of a thesis, and we know that the document has not been changed since it arrived on paper in our library. In contrast to this, information about publication dates and versions of documents that are accessed over networks are extremely short-lived. The responsibility for these documents remains with the author or publisher and thus they can be changed by them, if deemed appropriate. The dynamic nature of networked documents leads to the dilemma of up-to-date information versus access to the original version. Von Ungern-Sternberg and Lindquist (1995) pointed out that another concern is the authenticity or integrity of electronic documents. Once a document is stored on a computer, it can be relatively easily manipulated by additions, deletions or changes. ``A number of `digital signatures' or `electronic seals' based on cryptographic techniques'' may help to ensure authenticity. If electronic books are delivered offline (e.g., on diskettes, CD-ROMs or their successors), the difficulties of version control and validation of authenticity diminish. However, offline publications cannot be updated as easily as networked documents, and they don't exploit the capability of interlinking with external resources. Instead, hypertext links are used to navigate within the document or in order to make use of built-in multimedia effects like sound, video, and simulations.
Although an unlimited number of copies can be downloaded or printed from electronic books, assuming the electronic version is free-of-charge or the access fee has been paid, nevertheless electronic books can become unavailable. Out-of-print material on paper almost always can be located in some way, most importantly through interlibrary loan, and therefore hardly ever disappears entirely. Online documents, in contrast, might be withdrawn by the authors or publishers and may never be found again.
On the Internet, it is astonishingly easy to become a ``publisher''. Everybody equipped with a networked terminal and a server has the opportunity to distribute information globally without any difficulty. While this can be seen as moving towards more democracy in a general context, it is a threat in scientific publishing, because quality standards are likely to decrease. Algorithms that try to match users' requests with available documents do not solve this problem, because ``prioritizing according to relevance won't give you a true measure of quality'' (Schwartz, 1996). Commercial publishers and learned societies therefore argue that a careful editing process is necessary to assure that only those documents which would pass the quality control for paper-based publication are published electronically. Unfortunately, such editing is one of the major cost factors of journal production which will not disappear even if the journal is available exclusively in electronic format.