@article{bwmeta1.element.zamlynska-71284625-b70e-4688-9f58-8edeb7a69aaf,
author = {Carlton J. Maxson},
title = {Semigroups of order-preserving partial endomorphisms on trees, I},
journal = {Colloquium Mathematicae},
volume = {31},
year = {1974},
pages = {25-37},
zbl = {0269.20056},
language = {en},
url = {http://dml.mathdoc.fr/item/bwmeta1.element.zamlynska-71284625-b70e-4688-9f58-8edeb7a69aaf}
}
Carlton J. Maxson. Semigroups of order-preserving partial endomorphisms on trees, I. Colloquium Mathematicae, Tome 31 (1974) pp. 25-37. http://gdmltest.u-ga.fr/item/bwmeta1.element.zamlynska-71284625-b70e-4688-9f58-8edeb7a69aaf/