Voir la notice de l'article provenant de la source Czech Digital Mathematics Library
@article{CMUC_1968__9_1_a8, author = {Havel, V\'aclav}, title = {Nets and groupoids. {II.}}, journal = {Commentationes Mathematicae Universitatis Carolinae}, pages = {87--93}, publisher = {mathdoc}, volume = {09}, number = {1}, year = {1968}, mrnumber = {0231275}, zbl = {0162.24002}, language = {en}, url = {http://geodesic.mathdoc.fr/item/CMUC_1968__9_1_a8/} }
Havel, Václav. Nets and groupoids. II.. Commentationes Mathematicae Universitatis Carolinae, Tome 09 (1968) no. 1, pp. 87-93. http://geodesic.mathdoc.fr/item/CMUC_1968__9_1_a8/