Columbia subject headings:
Galaxies--Evolution--Congresses.
Galaxies--Formation--Congresses.
Molecular clouds--Congresses.
Stars--Formation--Congresses.
Harvard subject headings:
Galaxies--Evolution--Congresses
Molecular clouds--Congresses.
Stars--Formation--Congresses
Princeton subject headings:
Beckman, J. E.
Galaxies--Evolution.
Molecular clouds.
Stars--Formation.