Pion-nucleon charge exchange amplitudes above 2 GeV F. Huang, A. Sibirtsev, S. Krewald, C. Hanhart, J. Haidenbauer and U. -G. Meißner Eur. Phys. J. A, 40 1 (2009) 77-87 Published online: 19 February 2009 DOI: 10.1140/epja/i2008-10728-9