@article{GDZPPN002058308, title = {Unions and intersectons in Homotopy Theory.}, journal = {Commentarii mathematici Helvetici}, volume = {38}, year = {1963}, pages = {293-307}, zbl = {0126.38903}, url = {http://dml.mathdoc.fr/item/GDZPPN002058308} }
Eckmann, B.; Hilton, P.J. Unions and intersectons in Homotopy Theory.. Commentarii mathematici Helvetici, Tome 38 (1963) pp. 293-307. http://gdmltest.u-ga.fr/item/GDZPPN002058308/