High-order subharmonic parametric resonance of nonlinearly coupled micromechanical oscillators J. Zhu, C. Q. Ru and A. Mioduchowski Eur. Phys. J. B, 58 4 (2007) 411-421 Published online: 22 September 2007 DOI: 10.1140/epjb/e2007-00250-0