TY - JOUR AU - N. G. Khor'kova TI - Conservation laws and nonlocal symmetries JO - Matematičeskie zametki PY - 1988 SP - 134 EP - 144 VL - 44 IS - 1 PB - mathdoc UR - http://geodesic.mathdoc.fr/item/MZM_1988_44_1_a13/ LA - ru ID - MZM_1988_44_1_a13 ER -