Synchronization of geometric stochastic resonance by a bi-harmonic drive Martin P. Read, Russell Glavey, Fabio Marchesoni and Sergey E. Savel’ev Eur. Phys. J. B, 87 9 (2014) 206 Published online: 10 September 2014 DOI: 10.1140/epjb/e2014-50304-1