TOLLO, Ivy Pearl. Improving Underhand Serve Accuracy in Volleyball Using Arm Strengthening and Core Stability Exercises. USFD Journal of Physical Education Pedagogy & Sports Performance, Cagayan de Oro City, Philippines, v. 2, n. 2, p. 180–189, 2026. DOI: 10.64339/USFD-2zxrgt78. Disponível em: https://usfd-ph.org/ojs/index.php/usfd-jpepsp/article/view/38. Acesso em: 3 jul. 2026.