Pérez, Marta
Schleissner, Carmen
Fernández, Rogelio
Rodríguez, Pilar
Reyes, Fernando
Zuñiga, Paz
de la Calle, Fernando
Cuevas, Carmen
Article History
Received: 2 July 2015
Revised: 15 October 2015
Accepted: 28 October 2015
First Online: 9 December 2015
Competing interests
: The authors declare no conflict of interest.
Free to read: This content has been made available to all.