Evaluation of organic sub-monolayers by X-ray based measurements under gracing incident conditions O. Werzer, B. Stadlober, A. Haase, H.-G. Flesch and R. Resel Eur. Phys. J. Appl. Phys., 46 2 (2009) 20403 Published online: 27 March 2009 DOI: 10.1051/epjap/2009038