Columbia subject headings:
Kamlah, Wilhelm--Congresses.
Language and languages--Philosophy--Congresses.
Logic--Congresses.
Lorenzen, Paul, 1915-1994--Congresses.
Mathematics--Congresses.
Science--Philosophy--Congresses.
Harvard subject headings:
Constructivism (Philosophy)--Congresses.
Kamlah, Wilhelm--Congresses.
Lorenzen, Paul, 1915-1994--Congresses.
Princeton subject headings:
Constructivism (Philosophy)--Congresses.
Kamlah, Wilhelm--Congresses.
Lorenzen, Paul, 1915-1994--Congresses.