Voir la notice de l'article provenant de la source European Digital Mathematics Library
@article{CMH_1941__14_138787, author = {Beno Eckmann}, title = {\"Uber die {Homotopiegruppen} von {Gruppenr\"aumen.}}, journal = {Commentarii mathematici Helvetici}, pages = {234--256}, publisher = {mathdoc}, volume = {14}, year = {1941}, zbl = {0027.26502}, url = {http://geodesic.mathdoc.fr/item/CMH_1941__14_138787/} }
Beno Eckmann. Über die Homotopiegruppen von Gruppenräumen.. Commentarii mathematici Helvetici, Tome 14 (1941), pp. 234-256. http://geodesic.mathdoc.fr/item/CMH_1941__14_138787/