530 Subfield $3 - Materials specified:

Subfield $3 contains information that indicates the part of the described material to which the field applies.

Examples:

530 ##$3Diaries and correspondence$aAvailable in microfilm;$cFor use in repository only.

530 ##$3Ethnic enrollment study data$aAvailable in computer file and in computer output microfiche;$bState Historical Society of Wisconsin, Madison, WI 53706.