Martín-Ponce, Esther
Hernández-Betancor, Iván
González-Reimers, Emilio
Hernández-Luis, Rubén
Martínez-Riera, Antonio
Santolaria, Francisco
Article History
Received: 11 September 2014
Accepted: 20 November 2014
First Online: 22 December 2014
Competing interests
: The authors declare no competing financial interests.