@article{DE_2004_40_9_a11,
     author = {I. K. Lifanov and S. L. Stavtsev},
     title = {Integral equations and sound propagation in a shallow sea},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1256--1270},
     publisher = {mathdoc},
     volume = {40},
     number = {9},
     year = {2004},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_2004_40_9_a11/}
}