Kaufer-Horwitz, M
Villa, M
Pedraza, J
Domínguez-García, J
Vázquez-Velázquez, V
Méndez, J P
García-García, E
Article History
Received: 22 November 2013
Revised: 1 April 2014
Accepted: 19 April 2014
First Online: 4 June 2014
Competing interests
: The authors declare no conflict of interest.