@article{VSGTU_2014_135_2_a4,
     author = {T. H. Rasulov and E. B. Dilmurodov},
     title = {Investigations of the {Numerical} {Range} of a {Operator} {Matrix}},
     journal = {Journal of Samara State Technical University, Ser. Physical and Mathematical Sciences},
     pages = {50--63},
     year = {2014},
     volume = {135},
     number = {2},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/VSGTU_2014_135_2_a4/}
}