@article{GDZPPN002056941, title = {Cohomology Operations Derived from the Symmetric Group.}, journal = {Commentarii mathematici Helvetici}, volume = {30}, year = {1956}, pages = {195-218}, zbl = {0077.16701}, url = {http://dml.mathdoc.fr/item/GDZPPN002056941} }
Steenrod, N.E. Cohomology Operations Derived from the Symmetric Group.. Commentarii mathematici Helvetici, Tome 30 (1956) pp. 195-218. http://gdmltest.u-ga.fr/item/GDZPPN002056941/