scientific article

scientific article PNAS version

scientific article published in Annals of Mathematics in 1949

scientific article published in 1956

scientific article published in 1958

scientific article published in 1943

scientific article

scientific article published in 1944

scientific article published in 1939

scientific article published in 1965

scientific article published in 1942

doctoral dissertation and scientific article published in 1936 by Norman Steenrod