@article{GDZPPN001257390,
title = {Residual finiteness in permutation varieties of semigroups.},
journal = {Semigroup forum},
volume = {31},
year = {1985},
pages = {33-46},
zbl = {0552.20041},
url = {http://dml.mathdoc.fr/item/GDZPPN001257390}
}
Nordahl, T. Residual finiteness in permutation varieties of semigroups.. Semigroup forum, Tome 31 (1985) pp. 33-46. http://gdmltest.u-ga.fr/item/GDZPPN001257390/