1. Information theory and an extension of the maximum likelihood principle;Akaike,1973
2. A new look at the statistical model identification;Akaike;IEEE Trans. Autom. Control,1974
3. Splines (with optimal knots) are better;Burchard;Appl. Anal.,1974
4. Least Squares Cubic Spline Approximation. I: Fixed Knots CSD TR 20;de Boor,1968
5. Least squares cubic spline approximation. II: variable knots. CSD TR 21;de Boor,1968