APA (7th ed.) Citation

Pontrjagin, L. S. (1949). Vector Fields on manifolds. American Math. Soc.

Chicago Style (17th ed.) Citation

Pontrjagin, Lev S. Vector Fields on Manifolds. New York: American Math. Soc, 1949.

MLA (9th ed.) Citation

Pontrjagin, Lev S. Vector Fields on Manifolds. American Math. Soc, 1949.