@article{GDZPPN001247808,
title = {On (0,1)-matrix semigroups.},
journal = {Semigroup forum},
volume = {2},
year = {1971},
pages = {74-79},
zbl = {0228.20059},
url = {http://dml.mathdoc.fr/item/GDZPPN001247808}
}
Butler, K.K.H. On (0,1)-matrix semigroups.. Semigroup forum, Tome 2 (1971) pp. 74-79. http://gdmltest.u-ga.fr/item/GDZPPN001247808/