Garaigordobil, Maite, and José Ignacio Pérez. 2007. “Self-Concept, Self-Esteem and Psychopathological Symptoms in Persons with Intellectual Disability”. The Spanish Journal of Psychology 10, nº 1:: 141-50. https://revistas.ucm.es/index.php/SJOP/article/view/SJOP0707120141A