@article{SF_1972__5_133952,
     author = {M.S. Putcha},
     title = {Semigroups in which a power of each element lies in a subgroup.},
     journal = {Semigroup forum},
     pages = {354--361},
     publisher = {mathdoc},
     volume = {5},
     year = {1972},
     zbl = {0259.20052},
     url = {http://geodesic.mathdoc.fr/item/SF_1972__5_133952/}
}