M. S. Fudin, M. F. H. I. Fikri, N. Febrianto, and S. Sulendro, “The Effect of Interval Training on Cardiovascular Endurance and Agility of Students in Futsal Extracurricular SMK Negeri 1 Trenggalek”, Ina. Indones. J. Sport. Heal. Phys. Educ. Sci., vol. 3, no. 3, pp. 122–128, Oct. 2025.