@article{DAN_1987_296_5_a5,
     author = {L. A. Sakhnovich},
     title = {Spectral problems for systems of equations on the axis},
     journal = {Doklady Akademii Nauk},
     pages = {1052--1056},
     publisher = {mathdoc},
     volume = {296},
     number = {5},
     year = {1987},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1987_296_5_a5/}
}