@article{02221874,
title = {Discrete Morse theory and graph braid groups.},
journal = {Geometry \& Topology},
volume = {5},
year = {2005},
pages = {1075-1109},
doi = {10.2140/agt.2005.5.1075},
zbl = {1134.20050},
language = {en},
url = {http://dml.mathdoc.fr/item/02221874}
}
Farley, Daniel; Sabalka, Lucas. Discrete Morse theory and graph braid groups.. Geometry & Topology, Tome 5 (2005) pp. 1075-1109. doi : 10.2140/agt.2005.5.1075. http://gdmltest.u-ga.fr/item/02221874/