D. A. de Waal, S. E. S. Campher, & J. V. du Toit. (2012). Estimating Those Transformations That Produce the Best-fitting Additive Model: Smoothers Versus Universal Approximators. International Journal of Computer Information Systems and Industrial Management Applications, 4, 9. Retrieved from https://cspub-ijcisim.org/index.php/ijcisim/article/view/145