Marques M.M., de Gucht V., Leal I., Maes S. (2017). Efficacy of a randomized controlled brief physical activity self-regulation intervention for chronic fatigue: Mediation effects of physical activity progress and self-regulation skills. Journal of Psychosomatic Research, 94:24-31. DOI:10.1016/j.jpsychores.2016.12.012.