Columbia subject headings:
Differential equations, Partial.
Galois theory.
Geometry, Algebraic.
Geometry, Differential.
Harvard subject headings:
Differential equations, Partial.
Galois theory.
Geometry, Algebraic.
Geometry, Differential.
Princeton subject headings:
Differential equations, Partial.
Galois theory.
Geometry, Algebraic.
Geometry, Differential.