Hernández Hernández, E., P. Caballero Blanco, A. Gómez Rodríguez, and J. Morenas Martín. “Design and Validation of an Observational Instrument to Assess the Technical Execution in Top-Rope Climbing”. Journal of Human Sport and Exercise, vol. 9, no. 1, June 2014, pp. 111-23, doi:10.4100/jhse.2014.91.12.