ali, abass. “Employment of Exercises With Distances Less Than the Distance Race for Developing Copayments Endurance Speed and Effect That on Achieving 400m Running for Junior”. Journal of Physical Education 22, no. 4 (December 28, 2010): 31. Accessed May 9, 2024. https://jcope.uobaghdad.edu.iq/index.php/jcope/article/view/1695.