@article{RM_1993_48_1_a13,
     author = {Nguyen Van Lyong},
     title = {The spectral properties of a~quadratic pencil of operators},
     journal = {Trudy Matematicheskogo Instituta imeni V.A. Steklova},
     pages = {180--182},
     publisher = {mathdoc},
     volume = {48},
     number = {1},
     year = {1993},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/RM_1993_48_1_a13/}
}