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\bibitem{San_etal1990} San, L., Cam{\'\i}, J., Peri, J. M., Mata, R., \& Porta, M. (1990). Efficacy of clonidine, guanfacine and methadone in the rapid detoxification of heroin addicts : a controlled clinical trial. \textit{British journal of addiction}, \textit{85}(1; 01/1990), 141--147.

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