@article{DAN_1960_135_4_a2,
     author = {V. A. Il'in and I. A. Shishmarev},
     title = {Some problems for the $Lu=\operatorname{div}[p(x)\operatorname{grad}u]-q(x)u$ operator with discontinuous coefficients},
     journal = {Doklady Akademii Nauk},
     pages = {775--778},
     publisher = {mathdoc},
     volume = {135},
     number = {4},
     year = {1960},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1960_135_4_a2/}
}