Optimization of the focused flux of high harmonicsS. Kazamias, D. Douillet, C. Valentin, Th. Lefrou, G. Grillon, G. Mullot, F. Augé, P. Mercère, Ph. Zeitoun and Ph. BalcouEur. Phys. J. D, 26 1 (2003) 47-50DOI: https://doi.org/10.1140/epjd/e2003-00083-y