Columbia subject headings:
Authors, German--Germany--North Rhine-Westphalia--Directories.
Booksellers and bookselling--Germany--North Rhine-Westphalia--Directories.
German literature--Germany--North Rhine-Westphalia--Societies, etc.--Directories.
Publishers and publishing--Germany--North Rhine-Westphalia--Directories.
Harvard subject headings:
Authors, German--Germany--North Rhine-Westphalia--Directories.
Booksellers and bookselling--Germany--North Rhine-Westphalia--Directories.
German literature--Germany--North Rhine-Westphalia--Societies, etc.--Directories.
Publishers and publishing--Germany--North Rhine-Westphalia--Directories.
Princeton subject headings:
Authors, German--Germany--North Rhine-Westphalia--Directories.
German literature--Germany--North Rhine-Westphalia--Directories.