@article{02000804, title = {Finite subset spaces of graphs and punctured surfaces.}, journal = {Geometry \& Topology}, volume = {7}, year = {2003}, pages = {873-904}, doi = {10.2140/agt.2003.3.873}, zbl = {1032.55014}, language = {en}, url = {http://dml.mathdoc.fr/item/02000804} }
Tuffley, Christopher. Finite subset spaces of graphs and punctured surfaces.. Geometry & Topology, Tome 7 (2003) pp. 873-904. doi : 10.2140/agt.2003.3.873. http://gdmltest.u-ga.fr/item/02000804/