@article{CRMATH_2012__350_7-8_399_0,
     author = {Fabrizio Colombo and Irene Sabadini},
     title = {On some notions of spectra for quaternionic operators and for \protect\emph{n}-tuples of operators},
     journal = {Comptes Rendus. Math\'ematique},
     pages = {399--402},
     publisher = {Elsevier},
     volume = {350},
     number = {7-8},
     year = {2012},
     doi = {10.1016/j.crma.2012.03.017},
     language = {en},
}