@article{GDZPPN001250817,
title = {Idempotent Endomorphisms on Standard Threads.},
journal = {Semigroup forum},
volume = {11},
year = {1975},
pages = {14-21},
zbl = {0299.20053},
url = {http://dml.mathdoc.fr/item/GDZPPN001250817}
}
AKST, G.; Dence, T.P. Idempotent Endomorphisms on Standard Threads.. Semigroup forum, Tome 11 (1975) pp. 14-21. http://gdmltest.u-ga.fr/item/GDZPPN001250817/