@article{GDZPPN00036326X, title = {On Lattices with M\"obius Function $\pm$1, 0.}, journal = {Discrete \& computational geometry}, volume = {2}, year = {1987}, pages = {1-8}, url = {http://dml.mathdoc.fr/item/GDZPPN00036326X} }
Kahn, J. On Lattices with Möbius Function ±1, 0.. Discrete & computational geometry, Tome 2 (1987) pp. 1-8. http://gdmltest.u-ga.fr/item/GDZPPN00036326X/