@article{SF_1972__4_133897,
     author = {L. King},
     title = {Actions of a noncompact semigroup with zero.},
     journal = {Semigroup forum},
     pages = {224--231},
     year = {1972},
     volume = {4},
     zbl = {0256.54021},
     url = {http://geodesic.mathdoc.fr/item/SF_1972__4_133897/}
}