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@article{CM_1974__29_3_223_0, author = {Stong, R. E.}, title = {Semi-characteristics and free group actions}, journal = {Compositio Mathematica}, pages = {223--248}, publisher = {Noordhoff International Publishing}, volume = {29}, number = {3}, year = {1974}, mrnumber = {377943}, zbl = {0294.57021}, language = {en}, url = {http://geodesic.mathdoc.fr/item/CM_1974__29_3_223_0/} }
Stong, R. E. Semi-characteristics and free group actions. Compositio Mathematica, Tome 29 (1974) no. 3, pp. 223-248. http://geodesic.mathdoc.fr/item/CM_1974__29_3_223_0/