@article{SF_1972__4_133875,
     author = {P.S. Venkatesan},
     title = {Bisimple left inverse semigroups.},
     journal = {Semigroup forum},
     pages = {34--45},
     year = {1972},
     volume = {4},
     zbl = {0275.20114},
     url = {http://geodesic.mathdoc.fr/item/SF_1972__4_133875/}
}