Vision of a fully laser-driven nγ−mγ collider D. Habs, B. M. Hegelich, J. Schreiber and P. G. Thirolf Eur. Phys. J. D, 55 2 (2009) 253-264 Published online: 13 March 2009 DOI: 10.1140/epjd/e2009-00080-2