Naclerio Ayllón, Fernando, and Daniel Forte Fernández. “The Abdominal Muscles Function and Training: A Scientific Approach”. Journal of Human Sport and Exercise 1, no. 1 (December 3, 2008): 15–23. Accessed April 23, 2024. https://www.jhse.ua.es/article/view/2006-v1-n1-funcion-y-entrenamiento-de-la-musculatura-abdominal-u.