@article{SF_1985__32_134764, author = {G. Hansoul and J. Varlet}, title = {Perfect semilattices.}, journal = {Semigroup forum}, pages = {23--30}, publisher = {mathdoc}, volume = {32}, year = {1985}, language = {en}, url = {http://geodesic.mathdoc.fr/item/SF_1985__32_134764/} }