Operator product expansion and quark condensate from lattice QCD in coordinate space V. Gimenez, V. Lubicz, F. Mescia, V. Porretti and J. Reyes Eur. Phys. J. C, 41 4 (2005) 535-544 Published online: 15 June 2005 DOI: 10.1140/epjc/s2005-02250-9