Dispersion relation formalism for virtual Compton scattering off the proton B. Pasquini, M. Gorchtein, D. Drechsel, A. Metz and M. Vanderhaeghen Eur. Phys. J. A, 11 2 (2001) 185-208 Published online: 15 June 2001 DOI: 10.1007/s100500170084