TY  - JOUR
AU  - V. V. Velichenko
TI  - The invariance of discrete systems
JO  - Doklady Akademii Nauk
PY  - 1969
SP  - 503
EP  - 506
VL  - 185
IS  - 3
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DAN_1969_185_3_a2/
LA  - ru
ID  - DAN_1969_185_3_a2
ER  -