Always give the numbering for the earliest available issue in field 588, preceded by the words Description based on. This . his field must be given for all descriptions of serials even if it is the issue cited in the 362 1# and the “Latest issue consulted” note. Include the numbering of the earliest issue in hand. If there is no chronological designation, give the publishing date in addition to the numerical designation in order to supply some indication of the time frame. When a numeric designation alone is given in a "Description based on" note, add the date of publishing or copyright if possible. Former CONSER practice was to give the numbering for the earliest available issue preceded by the words Description based on text.
588 ## $a Description based on: No. 8, published in 1990; title from title page.
588 ## $a Description based on: No. 2, copyright 1989; title from caption.588 ##
Current practice is to omit the text and use 0 as the first indicate to enable the automatic display of the note.
588 0# $a Description based on: No. 2, copyright 1989; title from caption.
588 0# $a Description based on: 3, published 1989; title from cover?
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