@article{DE_1980_16_11_a12,
     author = {E. Kh. Khristov},
     title = {Expansion in products of the solutions of two {Sturm--Liouville} problems on the semiaxis},
     journal = {Differencialʹnye uravneni\^a},
     pages = {2023--2029},
     publisher = {mathdoc},
     volume = {16},
     number = {11},
     year = {1980},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1980_16_11_a12/}
}