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\bibitem{LeyvaPernia_etal2013} {\textquotedblleft}\textit{Study of the main physical processes contributing to image formation in emission radiography using mathematical modeling}{\textquotedblright}. Leyva Pernia D, Cabal Rodr{\'\i}guez AE, Schalm O, van Espen P, Pi{\~n}era Hern{\'a}ndez I, Abreu Alfonso Y,  (2013)

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