Másmela Caita, Luis Alejandro, and Álvaro Alexander Burbano Moreno. “Generalized Secant Hyperbolic and a Method of Estimate of Its Parameters: Maximum Likelihood Modified”. Ingeniería Y Ciencia, vol. 9, no. 18, Sept. 2013, pp. 93-106, https://doi.org/10.17230/ingciecia.9.18.5.