@article{1183514049, author = {Wallace, A. D.}, title = {Cyclic invariance under multi-valued maps}, journal = {Bull. Amer. Math. Soc.}, volume = {55}, number = {12}, year = {1949}, pages = { 820-824}, language = {en}, url = {http://dml.mathdoc.fr/item/1183514049} }
Wallace, A. D. Cyclic invariance under multi-valued maps. Bull. Amer. Math. Soc., Tome 55 (1949) no. 12, pp. 820-824. http://gdmltest.u-ga.fr/item/1183514049/