@article{FPM_2001_7_1_a18,
     author = {Yu. F. Pastukhov},
     title = {Necessary conditions in the~inverse variational problem},
     journal = {Fundamentalʹna\^a i prikladna\^a matematika},
     pages = {285--288},
     year = {2001},
     volume = {7},
     number = {1},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/FPM_2001_7_1_a18/}
}