Voir la notice de l'article provenant de la source Czech Digital Mathematics Library
@article{CMJ_2008__58_2_a1, author = {Descal\c{c}o, L. and Ru\v{s}kuc, N.}, title = {Properties of the subsemigroups of the bicyclic monoid}, journal = {Czechoslovak Mathematical Journal}, pages = {311--330}, publisher = {mathdoc}, volume = {58}, number = {2}, year = {2008}, mrnumber = {2411092}, zbl = {1166.20052}, language = {en}, url = {http://geodesic.mathdoc.fr/item/CMJ_2008__58_2_a1/} }
Descalço, L.; Ruškuc, N. Properties of the subsemigroups of the bicyclic monoid. Czechoslovak Mathematical Journal, Tome 58 (2008) no. 2, pp. 311-330. http://geodesic.mathdoc.fr/item/CMJ_2008__58_2_a1/