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\bibitem{vanEspen_etal1986} {\textquotedblleft}\textit{AXIL-PC, software for the analysis of complex-x-ray spectra}{\textquotedblright}. van Espen P, Janssens K, Nobels J, Chemometrics and intelligent laboratory systems \textbf{1}, 109 (1986).   http://doi.org/10.1016/0169-7439(86)80031-4

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