Li, Rong, and Weicheng Cui. “Harnessing Active Force: The Pumping Mechanism of Child’s Swing Motion”. European Journal of Applied Sciences 12, no. 4 (July 29, 2024): 164–182. Accessed February 4, 2026. https://www.journals.scholarpublishing.org/index.php/AIVP/article/view/17314.