APA (7th ed.) Citation

Pontrjagin, L. S. (1951). Some topological invariants of closed Riemannian manifolds.

Chicago Style (17th ed.) Citation

Pontrjagin, Lev S. Some Topological Invariants of Closed Riemannian Manifolds. Providence, RI, 1951.

MLA (9th ed.) Citation

Pontrjagin, Lev S. Some Topological Invariants of Closed Riemannian Manifolds. 1951.

Warning: These citations may not always be 100% accurate.