Trejo-Hernández, Abigail
Andrade-Domínguez, Andrés
Hernández, Magdalena
Encarnación, Sergio
Article History
Received: 19 September 2013
Revised: 6 March 2014
Accepted: 9 March 2014
First Online: 17 April 2014
Competing interests
: The authors declare no conflict of interest.
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