@article{TRSPY_1968_96_a9,
     author = {M. N. Yakovlev},
     title = {Nonnegative solutions of boundary-value problems for quasilinear second-order equations},
     journal = {Informatics and Automation},
     pages = {105--110},
     publisher = {mathdoc},
     volume = {96},
     year = {1968},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TRSPY_1968_96_a9/}
}