@article{05050785,
title = {Hard squares with negative activity and rhombus tilings of the plane.},
journal = {The Electronic Journal of Combinatorics [electronic only]},
volume = {13},
year = {2006},
zbl = {1096.05004},
language = {en},
url = {http://dml.mathdoc.fr/item/05050785}
}
Jonsson, Jakob. Hard squares with negative activity and rhombus tilings of the plane.. The Electronic Journal of Combinatorics [electronic only], Tome 13 (2006) . http://gdmltest.u-ga.fr/item/05050785/