A. Arimbi, P. Patmawati, S. Silatulrahmi, and N. Nurliani, “Fartlek Training on the Improvement of Hemoglobin Conditions and Hematocrit”, IJSBAR, vol. 38, no. 2, pp. 42–46, May 2018, Accessed: Feb. 06, 2026. [Online]. Available: https://gssrr.org/JournalOfBasicAndApplied/article/view/8836