Callejo, J., T. Aguado, B. Ballesteros, I. Gil Jaurena, and B. López. “EVALUATION INDICATORS IN DISTANCE EDUCATION AT THE UNIVERSITY SYSTEM”. RIED. Revista Iberoamericana de Educación a Distancia, vol. 4, no. 1, June 2001, pp. 35-50, doi:10.5944/ried.4.1.1190.