1.
GANI, Ruslan Abdul, TANGKUDUNG, James and DLIS, Firmansyah. Development Exercise Model In Butterfly Swimming For Athletesin The Age Group 11-13 Years Based on Drill Throught Android App. Journal of Education, Health and Sport. Online. 1 July 2019. Vol. 9, no. 6, pp. 376-387. [Accessed 1 December 2023].