@article{SF_1978__16_134294,
     author = {T.E. Nordahl and H.E. Scheiblich},
     title = {Regular * semigroups.},
     journal = {Semigroup forum},
     pages = {369--378},
     publisher = {mathdoc},
     volume = {16},
     year = {1978},
     zbl = {0408.20043},
     url = {http://geodesic.mathdoc.fr/item/SF_1978__16_134294/}
}