@article{ELA_2007__16__a8,
     author = {Li, Chi-Kwong and Poon, Edward and Rastogi, Ashwin},
     title = {Maps preserving spectral radius, numerical radius, spectral norm},
     journal = {The electronic journal of linear algebra},
     pages = {347--365},
     publisher = {mathdoc},
     volume = {16},
     year = {2007},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/ELA_2007__16__a8/}
}