Paula Born Lopes, Luana Loss Cabral, Robert J Robertson, Andrea Holtz Franco, and Gleber Pereira. “A Systematic Review of Validity and Reliability of Perceived Exertion Scales to Older Adults”. Revista de Psicología del Deporte (Journal of Sport Psychology) 29, no. 4 (February 28, 2021): 74–89. Accessed December 22, 2024. https://rpd-online.com/index.php/rpd/article/view/230.