@article{SF_1972__4_133880,
     author = {C.J. Maxson},
     title = {On semigroups of {Boolean} ring endomorphisms.},
     journal = {Semigroup forum},
     pages = {78--82},
     year = {1972},
     volume = {4},
     zbl = {0262.06011},
     url = {http://geodesic.mathdoc.fr/item/SF_1972__4_133880/}
}