@article{1183514553, author = {Weyl, Hermann}, title = {Ramifications, old and new, of the eigenvalue problem}, journal = {Bull. Amer. Math. Soc.}, volume = {56}, number = {6}, year = {1950}, pages = { 115-139}, language = {en}, url = {http://dml.mathdoc.fr/item/1183514553} }
Weyl, Hermann. Ramifications, old and new, of the eigenvalue problem. Bull. Amer. Math. Soc., Tome 56 (1950) no. 6, pp. 115-139. http://gdmltest.u-ga.fr/item/1183514553/