@article{10_4064_sm_49_3_253_262,
     author = {GH. Mocanu},
     title = {The joint approximate spectrum of a finite system of elements of a {C*-algebra}},
     journal = {Studia Mathematica},
     pages = {253--262},
     publisher = {mathdoc},
     volume = {49},
     number = {3},
     year = {1973},
     doi = {10.4064/sm-49-3-253-262},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/sm-49-3-253-262/}
}