@article{MZM_1969_5_2_a12,
     author = {M. A. Krasnosel'skii and Yu. V. Pokornyi},
     title = {Non-zero solutions of equations with strong nonlinearities},
     journal = {Matemati\v{c}eskie zametki},
     pages = {253--260},
     publisher = {mathdoc},
     volume = {5},
     number = {2},
     year = {1969},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1969_5_2_a12/}
}