Voir la notice de l'article provenant de la source Novi sad journal of mathematics website
@article{NSJOM_2004_34_2a_2, author = {C. M. Campbell and P. P. Campbell}, title = {On the minimal length of semigroup presentations}, journal = {Novi Sad Journal of Mathematics}, pages = {17-26}, publisher = {mathdoc}, volume = {34}, number = {2}, year = {2004}, url = {http://geodesic.mathdoc.fr/item/NSJOM_2004_34_2a_2/} }
C. M. Campbell; P. P. Campbell. On the minimal length of semigroup presentations. Novi Sad Journal of Mathematics, Tome 34 (2004) no. 2. http://geodesic.mathdoc.fr/item/NSJOM_2004_34_2a_2/