@article{SM_2017_208_9_a1,
     author = {D. V. Valovik},
     title = {The spectral properties of some nonlinear operators of {Sturm-Liouville} type},
     journal = {Sbornik. Mathematics},
     pages = {1282--1297},
     publisher = {mathdoc},
     volume = {208},
     number = {9},
     year = {2017},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SM_2017_208_9_a1/}
}