@article{GDZPPN001252453,
title = {The admissable trace problem for E-unitary inverse semigroups.},
journal = {Semigroup forum},
volume = {14},
year = {1977},
pages = {235-246},
zbl = {0379.20050},
url = {http://dml.mathdoc.fr/item/GDZPPN001252453}
}
Byleen, K.; Komjáth, P. The admissable trace problem for E-unitary inverse semigroups.. Semigroup forum, Tome 14 (1977) pp. 235-246. http://gdmltest.u-ga.fr/item/GDZPPN001252453/