Differential geometry {For differential topology, see 57Rxx; for foundational questions of differentiable manifolds, see 58Axx} 120509

## Mathematics Subject Classification – MSC2020

History of differential geometry [Consider also classification numbers pertaining to Section 01-XX] 523

Integral geometry [See also 52A22, 60D05]; differential forms, currents, etc. [See mainly 58Axx] 2305