Pontryagin, L. S. (1952). Foundations of combinatorial topology. Graylock Press.
Lua i Stíl Chicago (17ú heag.)Pontryagin, L. S. Foundations of Combinatorial Topology. Rochester, N.Y: Graylock Press, 1952.
Lua MLA (9ú heag.)Pontryagin, L. S. Foundations of Combinatorial Topology. Graylock Press, 1952.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.