The designation area is sometimes more problematic for electronic serials than for standard print serials.  Use the 362 field for the designation when certain that the first issue published is in hand and there are no retrospective discs possible.

362 0# $a Disc #9309 (Jan. 1993 through Sept. 1993)-

If the first issue is not in hand, provide a "Description based on:" note, followed by the "title from ... " note (see also CCM 30.3.3.).

500 ## $a Description based on: 1983/#1-26, 1984/#1-26, 1985/#1-13; title from title screen.
(See Figure 30.3b.)

The "earliest" issue may be difficult to determine for electronic serials whose discs are cumulative.  When cataloging such a title, use a "Description based on:" note if you are unsure whether or not the cumulation being cataloged is the "earliest" one.

500 ## $a Description based on: 7/84-9/30/87; title from title screen.

Retrospective discs may likewise cause some difficulty in determining the "earliest" issue.  If the coverage of an electronic serial does not go back to the earliest coverage of the title in print, use a "Description based on:" note to describe the "earliest" issue in hand.

When a retrospective disc covering the entire print run of a serial has been received, CONSER catalogers may "back up" the 362 field and all other necessary fields to match the "earliest" retrospective disc:

362 0# $a Disc 1 (1785/1979)-

Use a 500 note to describe any discrepancies in publication date(s) caused by cumulative and/or retrospective discs (see CCM 10.6.3).  Explain retrospective disc(s) in a 515 note, if considered useful (see CCM 30.14.3).

Electronic serials may assume the numbering of their print counterparts:

362 0# $a 38th issue (1990/91)-

See also:

Module 30.  Direct Access Electronic Serials