Columbia subject headings:
Authors, French--20th century--Correspondence.
Gaspar, Lorand, 1925---Correspondence.
Perros, Georges--Correspondence.
Harvard subject headings:
Authors, French--20th century--Correspondence
Gaspar, Lorand, 1925---Correspondence.
Perros, Georges--Correspondence.
Princeton subject headings:
Authors, French--20th century--Correspondence.
Perros, Georges--Correspondence.