Voir la notice de l'article provenant de la source European Digital Mathematics Library
@article{MZ_1965__87_170380, author = {Michel Andr\'e}, title = {Homotopy groups in categories.}, journal = {Mathematische Zeitschrift}, pages = {299--313}, publisher = {mathdoc}, volume = {87}, year = {1965}, zbl = {0127.13405}, url = {http://geodesic.mathdoc.fr/item/MZ_1965__87_170380/} }
Michel André. Homotopy groups in categories.. Mathematische Zeitschrift, Tome 87 (1965), pp. 299-313. http://geodesic.mathdoc.fr/item/MZ_1965__87_170380/