Columbia subject headings:
Astrophysics--Congresses.
General relativity (Physics)--Congresses.
Gravitation--Congresses.
Harvard subject headings:
Astrophysics--Congresses
General relativity (Physics)--Congresses.
Gravitation--Congresses
Princeton subject headings:
Astrophysics--Congresses.
General relativity (Physics)--Congresses.
Gravitation--Congresses.