Voir la notice de l'article provenant de la source European Digital Mathematics Library
@article{GMJ_1998__5_5_48189, author = {Mucuk, Osman}, title = {Coverings and ring-groupoids.}, journal = {Georgian Mathematical Journal}, pages = {475--482}, publisher = {mathdoc}, volume = {5}, number = {5}, year = {1998}, zbl = {0918.22002}, language = {en}, url = {http://geodesic.mathdoc.fr/item/GMJ_1998__5_5_48189/} }
Mucuk, Osman. Coverings and ring-groupoids.. Georgian Mathematical Journal, Tome 5 (1998) no. 5, pp. 475-482. http://geodesic.mathdoc.fr/item/GMJ_1998__5_5_48189/