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Candela A, Hernández L, Asensio S, Sánchez-Payá J, Vila J, Benito N, Romero S.Candela A, et al.Arch Bronconeumol. 2005 Feb;41(2):71-7. doi: 10.1016/s1579-2129(06)60400-x.Arch Bronconeumol. 2005.PMID: 15718000Spanish.