Binary Cepheids from optical interferometry A. Gallenne, P. Kervella, A. Mérand, J.D. Monnier, J. Breitfelder, G. Pietrzyński and W. Gieren EAS Publications Series, 64 (2013) 197-204 Published online: 25 February 2014 DOI: 10.1051/eas/1364027