Columbia subject headings:
Frege, Gottlob, 1848-1925--Congresses.
Mathematics--Congresses.
Mathematics--Philosophy--Congresses.
Harvard subject headings:
Arithmetic--Foundations--Congresses.
Mathematics--Philosophy--Congresses
Princeton subject headings:
Frege, Gottlob, 1848-1925--Congresses.
Mathematics--Congresses.
Mathematics--Philosophy--Congresses.