Plasma-based X-ray laser at 21 nm for multidisciplinary applications T. Mocek, B. Rus, M. Kozlová, J. Polan, P. Homer, K. Jakubczak, M. Stupka, D. Snopek, J. Nejdl, M. H. Edwards et al. (11 more) Eur. Phys. J. D, 54 2 (2009) 439-444 Published online: 06 February 2009 DOI: 10.1140/epjd/e2009-00021-1