@article{SMJ2_2015_41_4_a9,
     author = {Kutev, N. and Kolkovska, N. and Dimova, M.},
     title = {Finite {Time} {Blow} up of the {Solutions} to {Nonlinear} {Klein-Gordon} {Equation} with {Arbitrary} {High} {Positive} {Initial} {Energy}},
     journal = {Serdica Mathematical Journal},
     pages = {481--492},
     publisher = {mathdoc},
     volume = {41},
     number = {4},
     year = {2015},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SMJ2_2015_41_4_a9/}
}