Columbia subject headings:
Franck, Hans, 1879-1964--Correspondence.
Poets, German--Germany (East)--Correspondence.
Harvard subject headings:
Franck, Hans, 1879-1964--Correspondence.
Poets, German--20th century--Correspondence.
Poets, German--Germany (East)--Correspondence.
Princeton subject headings:
Franck, Hans, 1879-1964--Correspondence.
Personal correspondence.