Columbia subject headings:
Astrophysics--Mathematics--Congresses.
Dynamics--Congresses.
Nonlinear theories--Congresses.
Harvard subject headings:
Astrophysics--Mathematics--Congresses.
Dynamics--Congresses
Nonlinear theories--Congresses
Princeton subject headings:
Astrophysics--Mathematics--Congresses.
Dynamics--Congresses.
Nonlinear theories--Congresses.