Portillo, Javier, Javier Díaz-Lara, Alberto Pertíñez-Benítez, Miguel Villa-de Gregorio, Pablo Abián, Alfredo Bravo-Sánchez, and Javier Abián-Vicén. “Validation of an Assessment Instrument for Secondary School Teachers of a Co-Educational Sport (kin-Ball)”. Retos 70 (June 27, 2025): 269–279. Accessed November 7, 2026. https://www.revistaretos.org/index.php/retos/article/view/115148.