1. “Comparison of modeling calculations with experimental results for rf glow discharge optical emission spectrometry”. Bogaerts A, Wilken L, Hoffmann V, Gijbels R, Wetzig K, Spectrochimica acta: part B : atomic spectroscopy 57, 109 (2002).   http://doi.org/10.1016/S0584-8547(01)00357-3