@article{GDZPPN002405555, title = {Non-nilpotent Elements of Cohomology Rings.}, journal = {Mathematische Zeitschrift}, volume = {111}, year = {1969}, pages = {364-374}, zbl = {0179.32105}, url = {http://dml.mathdoc.fr/item/GDZPPN002405555} }
Johnson, David L. Non-nilpotent Elements of Cohomology Rings.. Mathematische Zeitschrift, Tome 111 (1969) pp. 364-374. http://gdmltest.u-ga.fr/item/GDZPPN002405555/