Members of the Association of Jewish Libraries.
This is the official roster of affiliates maintained by the organization. AJL members include active librarians working in the areas of Judaica and Jewish studies as well as many academics.
The AJL publishes a quarterly newsletter as well as the journal "Judaica librarianship", acclaimed by the library journal as "the most comprehensive of the professional journals".
Usage & counts: https://negevdirect.com/list/association-of-jewish-libraries/
