1. Inserting new knots into B-spline curves;Boehm;CAD,1980
2. C. de Boor, private communication.
3. On calculating with B-splines;de Boor;J. Approx. Theory,1972
4. Total Positivity of the Spline Collocation Matrix;de Boor;University of Wisconsin Mathematics Research Center Technical Report #1396,1973