Del Valle, Sagrario, et al. “Teorías Constructivistas, Perspectiva Funcional-Estructural En El Aprendizaje Del Fútbol Base (Constructivist Theories, Functional-Structural Perspective in Learning in Initiation to Football)”. Retos, vol. 38, July 2020, pp. 824-30, https://doi.org/10.47197/retos.v38i38.73823.