Light-polarization and intensity dependence of higher-order nonlinearities in excitonic FWM signalsM. Buck, L. Wischmeier, S. Schumacher, G. Czycholl, F. Jahnke, T. Voss, I. Rückmann and J. GutowskiEur. Phys. J. B, 42 2 (2004) 175-180DOI: https://doi.org/10.1140/epjb/e2004-00369-4