Optional Definition Note that describes the target audience of the item. The target audience is the persons, institutions, or individuals for whom the item is intended. Use field 521 if different versions, editions, or distributions exist with different contents or annotations. If both reading grade and interest age or grade level data is present in field 521, enter codes in Audn based on interest age or grade information. If the note is about restrictions on access, use field 506.
First indicator Controls the print constants.
Reading grade level. 1 Interest age level. 2 Interest grade level. 3 Special audience characteristics. The audience to which the items will most likely be of interest.