Menéndez, H
Ferrero, C
Martín-Hernández, J
Figueroa, A
Marín, P J
Herrero, A J
Article History
Received: 14 October 2015
Revised: 22 March 2016
Accepted: 24 March 2016
First Online: 3 May 2016
Competing interests
: The authors declare no conflict of interest.