@article{CHEB_2021_22_3_a20,
     author = {V. I. Gorbachev},
     title = {Problems on eigenvalues for ordinary differential equations of the second order with variable coefficients},
     journal = {\v{C}eby\v{s}evskij sbornik},
     pages = {353--367},
     publisher = {mathdoc},
     volume = {22},
     number = {3},
     year = {2021},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/CHEB_2021_22_3_a20/}
}