@article{DAN_1991_317_3_a0,
     author = {M. S. Almamedov and M. Bayramoglu and V. I. Katanova},
     title = {Trace formulas for an even-order differential equation with an},
     journal = {Doklady Akademii Nauk},
     pages = {521--525},
     publisher = {mathdoc},
     volume = {317},
     number = {3},
     year = {1991},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1991_317_3_a0/}
}