Aguirre Ospina, Oscar David, Ángela María Ríos Medina, Mauricio Calderón Marulanda, and Luz María Gómez Buitrago. 2014. “Cumulative Sum Learning Curves (CUSUM) in Basic Anaesthesia Procedures”. Colombian Journal of Anesthesiology 42 (3):142-53. https://www.revcolanest.com.co/index.php/rca/article/view/541.