Columbia subject headings:
Harvard subject headings:
Bok, Bart J. (Bart Jan), 1906-1983.
Cosmochemistry--Congresses.
Planets--Origin--Congresses.
Protostars--Congresses.
Solar system--Origin--Congresses.
Princeton subject headings:
Cosmochemistry--Congresses.
Planets--Origin--Congresses.
Protostars--Congresses.
Solar system--Origin--Congresses.