Álvarez, T., R. Codorniú, and I. Pina. “PI and PID Temperature and Product Concentration Control in a Chemical Plant Producing Propilenglicol”. ITEGAM-JETIA, Vol. 4, no. 14, June 2018, pp. 15-26, https://itegam-jetia.org/journal/index.php/jetia/article/view/25.