Columbia subject headings:
Deutsche Staatsbibliothek--Catalogs.
Jacobs, Emil, 1868-1940--Archives--Bibliography.
Jacobs, Emil, 1868-1940--Bibliography--Catalogs.
Harvard subject headings:
Deutsche Staatsbibliothek--Catalogs.
Jacobs, Emil, 1868-1940--Archives--Bibliography.
Jacobs, Emil, 1868-1940--Bibliography--Catalogs.
Princeton subject headings:
Jacobs, Emil, 1868-1940--Library--Catalogs.