Anggriawan, H., M. Doewes, and S. K. Purnama. “The Development of Badminton Blow Basic Exercise Model in Early Age 10-11 Years (through Exercise Drill Approach)”. Journal of Education, Health and Sport, vol. 8, no. 9, Sept. 2018, pp. 861-7, https://apcz.umk.pl/JEHS/article/view/5962.