R. Jiménez Boraita, J. M. Dalmau Torres, E. Gargallo Ibort, and D. Arriscado Alsina, “Diferencias en la percepción de actividad física en escolares de sexto de primaria (Differences in the perception of physical activity in sixth-grade primary school students)”, Retos, vol. 37, pp. 455–459, Jan. 2020, doi: 10.47197/retos.v37i37.71008.