Columbia subject headings:
Harvard subject headings:
Educators--Germany--Correspondence.
Patočka, Jan, 1907-1977--Correspondence.
Philosophers--Czech Republic--Correspondence.
Philosophers--Ukraine--Correspondence.
Schaller, Klaus, 1925---Correspondence.
Tschižewskij, Dmitrij, 1894-1977--Correspondence.
Princeton subject headings:
Patočka, Jan, 1907-1977--Correspondence.
Schaller, Klaus, 1925---Correspondence.
Tschižewskij, Dmitrij, 1894-1977.