Columbia subject headings:
Bergmann, Gustav, 1906-1987--Congresses.
Ontology--Congresses.
Harvard subject headings:
Bergmann, Gustav, 1906-1987--Congresses.
Ontology--Congresses.
Philosophy--Congresses
Princeton subject headings:
Bergmann, Gustav, 1906-1987--Congresses.
Ontology--Congresses.