@article{PPN362162808_0011+dmdlog6,
title = {Some Free Submonoids of the Free Monoid of Prefix Codes.},
journal = {Semigroup forum},
volume = {11},
year = {1975},
pages = {22-29},
zbl = {0299.94005},
url = {http://dml.mathdoc.fr/item/PPN362162808_0011+dmdlog6}
}
SHYR, H.J. Some Free Submonoids of the Free Monoid of Prefix Codes.. Semigroup forum, Tome 11 (1975) pp. 22-29. http://gdmltest.u-ga.fr/item/PPN362162808_0011+dmdlog6/