Columbia subject headings:
Mühsam, Erich, 1878-1934--Correspondence.
Harvard subject headings:
Authors, German--20th century--Correspondence
Mühsam, Erich, 1878-1934--Correspondence.
Princeton subject headings:
Authors, German--20th century--Biography.
Mühsam, Erich, 1878-1934--Correspondence.