@article{SF_1970__1_133797,
     author = {P.A. Grillet},
     title = {Cancellative commutative semigroups.},
     journal = {Semigroup forum},
     pages = {249--253},
     publisher = {mathdoc},
     volume = {1},
     year = {1970},
     zbl = {0211.33702},
     url = {http://geodesic.mathdoc.fr/item/SF_1970__1_133797/}
}