@article{MZM_1973_14_3_a4,
     author = {K. Kh. Boimatov},
     title = {Separation properties for {Sturm--Liouville} operators},
     journal = {Matemati\v{c}eskie zametki},
     pages = {349--359},
     publisher = {mathdoc},
     volume = {14},
     number = {3},
     year = {1973},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1973_14_3_a4/}
}