@article{IVM_1998_4_a5,
     author = {I. S. Lomov},
     title = {The basis property on compact sets of root functions of second-order differential operators},
     journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika},
     pages = {40--52},
     publisher = {mathdoc},
     number = {4},
     year = {1998},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/IVM_1998_4_a5/}
}