Towards a high-precision calculation for the pion-nucleus scattering lengths S. Liebig, V. Baru, F. Ballout, C. Hanhart and A. Nogga Eur. Phys. J. A, 47 5 (2011) 69 Published online: 31 May 2011 DOI: 10.1140/epja/i2011-11069-4