@article{MZ_1969__112_171248,
     author = {David L. Johnson},
     title = {Non-nilpotent {Elements} of {Cohomology} {Rings.}},
     journal = {Mathematische Zeitschrift},
     pages = {364--374},
     publisher = {mathdoc},
     volume = {112},
     year = {1969},
     zbl = {0179.32105},
     url = {http://geodesic.mathdoc.fr/item/MZ_1969__112_171248/}
}