@article{SF_1985__32_134779,
     author = {J. Almeida},
     title = {Some quasi-ordered classes of finite commutative semigroups.},
     journal = {Semigroup forum},
     pages = {189--200},
     publisher = {mathdoc},
     volume = {32},
     year = {1985},
     zbl = {0585.20032},
     url = {http://geodesic.mathdoc.fr/item/SF_1985__32_134779/}
}