TY - JOUR AU - E. V. Petrova TI - The number and stability of nonlinear parametric oscillations in a~system of weakly coupled oscillators with pendulum nonlinearity JO - Matematičeskie zametki PY - 1999 SP - 369 EP - 376 VL - 65 IS - 3 PB - mathdoc UR - http://geodesic.mathdoc.fr/item/MZM_1999_65_3_a4/ LA - ru ID - MZM_1999_65_3_a4 ER -