Library of Congress call numbers assigned by libraries other than LC itself have second indicator "4" to distinguish these numbers from LC-assigned call numbers. In 1995, RLG issued guidelines for the appropriate use of the 050 _4. We will continue to follow those guidelines strictly (see RLG Guidelines for Using 050 _4). In addition, the following are local guidelines for implementing 050 _4 that are not included in the RLG documentation.
Exclusions: Only call numbers using Library of Congress classification should be entered in the 050 _4. Therefore, RUL should not enter an 050 _4 for categories of materials that do not get LC call numbers, such as:
In addition, the RLG guidelines specify that the call number in 050 _4 should conform to LC practice. Therefore, the following types of call number are not appropriate for using the 050 _4, and the call number should be entered in the CALL or LCAL field of the holdings record, as has been the practice until now:
Workflow and Recommendations: It is recommended that:
Implementation: The use of 050 _4 at RUL will begin on October 16, 1995.
Prepared by Lida Sak and Rhonda Marker, September 26, 1995.
Updated by Melissa De Fino, May 28, 2009