@article{IM2_1967_1_2_a11,
     author = {M. Sh. Birman and S. B. \`Entina},
     title = {The stationary method in the abstract theory of scattering},
     journal = {Izvestiya. Mathematics },
     pages = {391--420},
     publisher = {mathdoc},
     volume = {1},
     number = {2},
     year = {1967},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/IM2_1967_1_2_a11/}
}