Dan -- My understanding (others in the know (specifically Regina Reynolds,
Les Hawkins or other ISSN folks) can correct me if I'm wrong) is that it
depends on whether it's the original publisher also making it available
(thus simultaneous publications, different eds. need different ISSN for
identification) or whether it's a secondary publisher (UMI, JSTOR) that's
making an electronic reproduction available (only needing a single ISSN).
The assumption is that a secondary publisher will not have rights to make
significant changes so content should be relatively close.  This policy
has been applied more or less successfully for microform reproductions for
years and I think the ISSN Network is trying to apply it to electronic
reproductions as well.  Unfortunately, microform reproduction is a
photomechanical process that generally assures faithful reproduction,
electronic reproduction isn't necessarily as faithful, even with pdf
files.

The fact that it's a pdf does not necessarily mean the content is the
same...these days it's often hard to tell which is "original" (pdf or
print) and which is reproduction.  Even with pdf, links to supplementary
material can be added.  Hopefully Regina can add her two cents on latest
thoughts from the ISSN Network on this.  Hope this helps.  --Steve

    Steve Shadle           shadle@u.washington.edu  *******
    Serials Cataloger                                *****
    University of Washington Libraries, Box 352900    ***
    Seattle, WA 98195               (206) 685-3983     *

On Wed, 30 Aug 2000, Dan Kniesner wrote:

> I'm aware that JSTOR versions of journals have the same ISSN as their
> print ed. counterparts.
>
> What about PDF versions of journals?  Are PDF versions considered
> close-enough reproductions of the print journals and therefore can use the
> same ISSN as the print editions?
>
> Thank you.  Apologies if this has been discussed before.  I know that
> ejournals generally need a different ISSN.
>
> Dan Kniesner
> Oregon Health Sciences University Library
> Portland Oregon
> kniesner@ohsu.edu