Columbia subject headings:
Geometry, Differential--Congresses.
Nonlinear theories--Congresses.
Quantum field theory--Congresses.
Harvard subject headings:
Geometry, Differential--Congresses.
Nonlinear theories--Congresses.
Quantum field theory--Congresses.
Princeton subject headings:
Geometry, Differential--Congresses.
Nonlinear theories--Congresses.
Quantum field theory--Congresses.