Syafri S. Improving agility and speed in playing soccer in first grade students in sd negeri no. 11 sungai apit kecataman sungai apit kabupaten siak. JIPS [Internet]. 2018 Mar. 22 [cited 2024 Dec. 22];2(1):67-76. Available from: https://e-journal.sastra-unes.com/index.php/JIPS/article/view/310