@article{MR_1995__44_a8,
     author = {Thanassis Chryssakis},
     title = {A -range and \ensuremath{\varphi}- spatial {Numerical} range of a {Tensor} },
     journal = {M\ensuremath{\alpha}\ensuremath{\theta}\ensuremath{\eta}\ensuremath{\mu}\ensuremath{\alpha}\ensuremath{\tau}\ensuremath{\iota}\ensuremath{\kappa}\ensuremath{\acute\eta} E\ensuremath{\pi}\ensuremath{\iota}\ensuremath{\theta}\ensuremath{\varepsilon}\ensuremath{\acute\omega}\ensuremath{\rho}\ensuremath{\eta}\ensuremath{\sigma}\ensuremath{\eta}
},
     pages = {71-85},
     publisher = {mathdoc},
     volume = {44},
     year = {1995},
     language = {gr},
     url = {http://geodesic.mathdoc.fr/item/MR_1995__44_a8/}
}