@article{DAN_1962_145_6_a6,
     author = {Yu. S. Kolesov and M. A. Krasnosel'skii},
     title = {Lyapunov stability and equations with concave operators},
     journal = {Doklady Akademii Nauk},
     pages = {1217--1220},
     publisher = {mathdoc},
     volume = {145},
     number = {6},
     year = {1962},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1962_145_6_a6/}
}