@article{2539, author = {Waterman, Alan G.}, title = {The free lattice with 3 generators over $N\_5$ }, journal = {Portugaliae mathematica}, volume = {26}, year = {1967}, pages = {285-288}, zbl = {0207.32104}, mrnumber = {0265235}, language = {en}, url = {http://dml.mathdoc.fr/item/2539} }
Waterman, Alan G. The free lattice with 3 generators over $N_5$ . Portugaliae mathematica, Tome 26 (1967) pp. 285-288. http://gdmltest.u-ga.fr/item/2539/