@article{M2AN_1986__20_3_427_0, author = {Crouzeix, Michel}, title = {A note on the complex and real operator norms of real matrices}, journal = {ESAIM: Mathematical Modelling and Numerical Analysis - Mod\'elisation Math\'ematique et Analyse Num\'erique}, pages = {427--428}, publisher = {AFCET - Gauthier-Villars}, volume = {20}, number = {3}, year = {1986}, zbl = {0609.15013}, mrnumber = {862785}, language = {en}, url = {archive.numdam.org/item/M2AN_1986__20_3_427_0/} }
Crouzeix, Michel. A note on the complex and real operator norms of real matrices. ESAIM: Mathematical Modelling and Numerical Analysis - Modélisation Mathématique et Analyse Numérique, Tome 20 (1986) no. 3, pp. 427-428. http://archive.numdam.org/item/M2AN_1986__20_3_427_0/