B. I. Díaz Pinargo, H. S. Comina Fonseca, and E. Romero Frómeta, “Endurance Index in Ecuadorian Youth Runners at Distances of 100-200, 200-400, 400-800 and 800-1500 Meters”, EFDeportes, vol. 26, no. 286, pp. 94-106, Mar. 2022.