1. The method of projections, etc;de Boor,1966
2. A note on local spline approximation by moments;de Boor;J. Math. Mech.,1968
3. On spline distributions and their limits: the Pólya distribution functions (abstract);Curry;Bull. Amer. Math. Soc.,1947
4. On Pólya frequency functions IV: The fundamental spline functions and their limits;Curry;J. d'Anal. Math.,1966