Bahrul , Ulum Muhammad, et al. “The Ability to Punch in the Front for Students of Pencak Silat Uns Achievement (Correlational Study Viewed from Eye-Hand Coordination, Arm Length and Arm Power)”. Health, Sport, Rehabilitation, vol. 6, no. 3, Sept. 2020, pp. 34-44, doi:10.34142/HSR.2020.06.03.04.