Backward pion photoproduction A. Sibirtsev, J. Haidenbauer, F. Huang, S. Krewald and U. -G. Meißner Eur. Phys. J. A, 40 1 (2009) 65-75 Published online: 31 March 2009 DOI: 10.1140/epja/i2008-10743-x