Quak, Ewald. “About B-Splines. Twenty Answers to One Question: What Is the Cubic B-Spline for the Knots -2,-1,0,1,2?”. J. Numer. Anal. Approx. Theory 45, no. 1 (September 19, 2016): 37–83. Accessed April 20, 2024. https://ictp.acad.ro/jnaat/journal/article/view/1099.