@article{05726995, title = {On groups and normal polymorphic functions.}, journal = {Revista Colombiana de Matem\'aticas}, volume = {42}, year = {2008}, pages = {167-181}, zbl = {1201.30050}, language = {en}, url = {http://dml.mathdoc.fr/item/05726995} }
Mejía, Diego; Pommerenke, Christian. On groups and normal polymorphic functions.. Revista Colombiana de Matemáticas, Tome 42 (2008) pp. 167-181. http://gdmltest.u-ga.fr/item/05726995/