@article{1183498782, author = {Walsh, J. L.}, title = {A necessary condition for approximation by rational functions}, journal = {Bull. Amer. Math. Soc.}, volume = {42}, number = {12}, year = {1936}, pages = { 219-221}, language = {en}, url = {http://dml.mathdoc.fr/item/1183498782} }
Walsh, J. L. A necessary condition for approximation by rational functions. Bull. Amer. Math. Soc., Tome 42 (1936) no. 12, pp. 219-221. http://gdmltest.u-ga.fr/item/1183498782/