@article{1256052951, author = {Becker, James C.}, title = {Extensions of cohomology theories}, journal = {Illinois J. Math.}, volume = {14}, number = {4}, year = {1970}, pages = { 551-584}, language = {en}, url = {http://dml.mathdoc.fr/item/1256052951} }
Becker, James C. Extensions of cohomology theories. Illinois J. Math., Tome 14 (1970) no. 4, pp. 551-584. http://gdmltest.u-ga.fr/item/1256052951/