@article{SF_1974__6_133962,
     author = {B.M. Schein},
     title = {Bands of unipotent monoids.},
     journal = {Semigroup forum},
     pages = {75--79},
     year = {1974},
     volume = {6},
     zbl = {0255.20044},
     url = {http://geodesic.mathdoc.fr/item/SF_1974__6_133962/}
}