@article{GDZPPN001253018,
title = {Spirals of idemopotents from P-semigroups.},
journal = {Semigroup forum},
volume = {18},
year = {1979},
pages = {95-100},
zbl = {0398.20065},
url = {http://dml.mathdoc.fr/item/GDZPPN001253018}
}
Byleen, K. Spirals of idemopotents from P-semigroups.. Semigroup forum, Tome 18 (1979) pp. 95-100. http://gdmltest.u-ga.fr/item/GDZPPN001253018/