Voir la notice de l'article provenant de la source European Digital Mathematics Library
@article{CMH_1969__44_139404, author = {John R. Harper}, title = {Stable {Secondary} {Cohomology} {Operations.}}, journal = {Commentarii mathematici Helvetici}, pages = {341--353}, publisher = {mathdoc}, volume = {44}, year = {1969}, zbl = {0199.33202}, url = {http://geodesic.mathdoc.fr/item/CMH_1969__44_139404/} }
John R. Harper. Stable Secondary Cohomology Operations.. Commentarii mathematici Helvetici, Tome 44 (1969), pp. 341-353. http://geodesic.mathdoc.fr/item/CMH_1969__44_139404/