TY  - JOUR
AU  - V. M. Filippov
AU  - V. M. Savchin
AU  - S. A. Budochkina
TI  - Bi-variationality, symmetries and approximate solutions
JO  - Contemporary Mathematics. Fundamental Directions
PY  - 2021
SP  - 596
EP  - 608
VL  - 67
IS  - 3
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/CMFD_2021_67_3_a12/
LA  - ru
ID  - CMFD_2021_67_3_a12
ER  -