Voir la notice de l'article provenant de la source European Digital Mathematics Library
@article{PORMA_1965__24_1_114937, author = {Henney, Dagmar R.}, title = {N-parameter semigroups}, journal = {Portugaliae mathematica}, pages = {31--37}, publisher = {mathdoc}, volume = {24}, number = {1}, year = {1965}, mrnumber = {0195981}, zbl = {0139.06803}, language = {en}, url = {http://geodesic.mathdoc.fr/item/PORMA_1965__24_1_114937/} }
Henney, Dagmar R. N-parameter semigroups. Portugaliae mathematica, Tome 24 (1965) no. 1, pp. 31-37. http://geodesic.mathdoc.fr/item/PORMA_1965__24_1_114937/