@article{1183425420, author = {Ritt, J. F.}, title = {Review: Michel Petrovitch, Les Spectres num\'eriques}, journal = {Bull. Amer. Math. Soc.}, volume = {27}, number = {3}, year = {1920}, pages = { 28-29}, language = {en}, url = {http://dml.mathdoc.fr/item/1183425420} }
Ritt, J. F. Review: Michel Petrovitch, Les Spectres numériques. Bull. Amer. Math. Soc., Tome 27 (1920) no. 3, pp. 28-29. http://gdmltest.u-ga.fr/item/1183425420/