@article{DAN_1985_283_6_a10,
     author = {V. E. Zakharov and E. I. Shulman},
     title = {The scattering matrix and integrability of classical wave systems},
     journal = {Doklady Akademii Nauk},
     pages = {1325--1328},
     publisher = {mathdoc},
     volume = {283},
     number = {6},
     year = {1985},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1985_283_6_a10/}
}