@article{1103038066, author = {Harmon, Sidney M.}, title = {Regular covering surfaces of Riemann surfaces.}, journal = {Pacific J. Math.}, volume = {10}, number = {4}, year = {1960}, pages = { 1263-1289}, language = {en}, url = {http://dml.mathdoc.fr/item/1103038066} }
Harmon, Sidney M. Regular covering surfaces of Riemann surfaces.. Pacific J. Math., Tome 10 (1960) no. 4, pp. 1263-1289. http://gdmltest.u-ga.fr/item/1103038066/