Tamayo, M., and F. Aleitte. “Compliance With Punctuality Guarantees (GES) for Technical Assistance in an Urban County of the Metropolitan Region”. Revista Chilena De Salud Pública, vol. 15, no. 3, Dec. 2011, pp. p. 146-154, https://revistaethika.uchile.cl/index.php/RCSP/article/view/17706.