@article{GDZPPN001250272, title = {Compatible extensions and subdirectly irreducible inverse semigroups.}, journal = {Semigroup forum}, volume = {7}, year = {1974}, pages = {241-252}, zbl = {0292.20057}, url = {http://dml.mathdoc.fr/item/GDZPPN001250272} }
Zitarelli, D.E. Compatible extensions and subdirectly irreducible inverse semigroups.. Semigroup forum, Tome 7 (1974) pp. 241-252. http://gdmltest.u-ga.fr/item/GDZPPN001250272/