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When the total number of units is uncertain or unknown, omit this information. This area does not have to be completed when closing off a record if the information is unavailable or difficult to determine.
300 ## $a volumes
Illustrations and other Content (300$b)
When providing a statement for the illustrative content for a serial, consider the whole serial. If it is likely that all or most issues will contain illustrations, record the statement. If only one, or an occasional issue, contains an illustration, omit the statement. Disregard title page illustrations and advertisements. If recording content other than or in addition to text, include a second content type (336) appropriate for the content
300 ## $a volumes : $b illustrations
300 ## $a text $b txt $2 rdacontent
300 ## $a still images $b sti $2 rdacontent