Pontri͡agin, L. S. 1908-1988. Foundations of combinatorial topology / by L.S. Pontryagin. - Rochester, N.Y. : Graylock Press, 1952. - xii, 99 p. ; 23 cm. Includes Index Subjects--Topical Terms: Combinatorial topology. Dewey Class. No.: 514.22 / PON 1952