Learn about the history of the 049 field, the communication format, and the OCLC number.
- History of field 049
- Find the history of field 049, including its placement in a bibliographic record, indicators, and repeatability.
- History of the communication format
- Find the history of the communication format from the 1974-2016.
- History of the OCLC number
- Find a brief description of the various forms of OCLC numbers that OCLC has output in OCLC-MARC via subscription and export from various OCLC cataloging services.