The emergence of local wrinkling or global buckling in thin freestanding bilayer films John F. Niven, Gurkaran Chowdhry, James S. Sharp and Kari Dalnoki-Veress Eur. Phys. J. E, 43 4 (2020) 20 Published online: 21 April 2020 DOI: 10.1140/epje/i2020-11946-y