@article{DE_1991_27_1_a9,
     author = {I. S. Lomov},
     title = {The basis property of root vectors of loaded second-order differential operators on an interval},
     journal = {Differencialʹnye uravneni\^a},
     pages = {80--93},
     publisher = {mathdoc},
     volume = {27},
     number = {1},
     year = {1991},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1991_27_1_a9/}
}