@article{bwmeta1.element.desklight-f09b752e-2787-4184-a2fd-d88291d822d2,
author = {Robert W. Quackenbush},
title = {Some classes of idempotent functions and their compositions},
journal = {Colloquium Mathematicae},
volume = {31},
year = {1974},
pages = {71-81},
zbl = {0247.04004},
language = {en},
url = {http://dml.mathdoc.fr/item/bwmeta1.element.desklight-f09b752e-2787-4184-a2fd-d88291d822d2}
}
Robert W. Quackenbush. Some classes of idempotent functions and their compositions. Colloquium Mathematicae, Tome 31 (1974) pp. 71-81. http://gdmltest.u-ga.fr/item/bwmeta1.element.desklight-f09b752e-2787-4184-a2fd-d88291d822d2/