D. Martín Espinosa, C. González González de Mesa, M. L. Zagalaz Sánchez, and J. J. Chinchilla Mira, “Extracurricular physical activities: Motivational climate, sportspersonship, disposition and context. A study with primary 6th grade students”, J. Hum. Sport Exerc., vol. 13, no. 2, pp. 466–486, Jun. 2018.