@article{10_4153_CJM_2000_007_2,
     author = {Li, Chi-Kwong and Tam, Tin-Yau},
     title = {Numerical {Ranges} {Arising} from {Simple} {Lie} {Algebras}},
     journal = {Canadian journal of mathematics},
     pages = {141--171},
     year = {2000},
     volume = {52},
     number = {1},
     doi = {10.4153/CJM-2000-007-2},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-2000-007-2/}
}