Columbia subject headings:
Disks (Astrophysics)--Congresses.
Galaxies--Congresses.
Milky Way--Congresses.
Harvard subject headings:
Disks (Astrophysics)--Congresses.
Galaxies--Congresses
Milky Way--Congresses.
Princeton subject headings:
Disks (Astrophysics)--Congresses.