@article{TM_2013_283_a2,
     author = {V. M. Filippov and V. M. Savchin and S. A. Budochkina},
     title = {On the existence of variational principles for differential--difference evolution equations},
     journal = {Trudy Matematicheskogo Instituta imeni V.A. Steklova},
     pages = {25--39},
     publisher = {mathdoc},
     volume = {283},
     year = {2013},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TM_2013_283_a2/}
}