Experimental determination of the scattering length for positron scattering from krypton A. Zecca, L. Chiari, E. Trainotti, D.V. Fursa, I. Bray and M.J. Brunger Eur. Phys. J. D, 64 2-3 (2011) 317-321 Published online: 11 October 2011 DOI: 10.1140/epjd/e2011-20333-7