Díaz-Barreiro, A
Bernal-Quirós, M
Georg, I
Marañón, C
Alarcón-Riquelme, M E
Castillejo-López, C
Article History
Received: 28 January 2015
Revised: 16 September 2015
Accepted: 8 December 2015
First Online: 28 January 2016
Competing interests
: The authors declare no conflict of interest.