Mid-infrared interferometric observations of four oxygen-rich Mira variables I. Karovicova, M. Wittkowski, K. Ohnaka, D.A. Boboltz, E. Fossat and M. Scholz EAS Publications Series, 63 (2013) 191-196 Published online: 19 December 2013 DOI: 10.1051/eas/1363022