Qusay, Waleed, and Laith Faris. “An Analysis of Some Motor Variables of Butterfly Stroke and Their Relationship to Success in the 50-Meter Butterfly Race for National Team Swimmers (candidate Category)”. Journal of Physical Education, vol. 34, no. 4, Dec. 2022, pp. 451-64, https://doi.org/10.37359/JOPE.V34(4)2022.1364.