- WorldCat knowledge base
- WorldShare Collection Manager
OCLC cannot guarantee that OCLC numbers (OCN's) in any collection are unique to just one item format type. Historically, publishers used one OCN for a title, regardless of multiple formats.
To check if the OCN is used for one or more formats of an item, download the collection's KBART file, sort in Excel to get a list of OCNs, then check the OCN in either WorldCat, Connexion Client, or WorldShare Record Manager to see if there is only one format type.