1. W. Baron, Zur trigonometrischen Interpolation, Computing 16 (1976), 319–328.
2. T. Lyche and R. Winther,A stable recurrence relation for trigonometric B-splines, to appear in J. of approximation theory.
3. Tom Lyche,A Newton form for trigonometric Hermite interpolation, Research Report 37, Institute of Informatics, University of Olso.
4. I. J. Schoenberg,On interpolation by spline functions and its minimal properties, inOn Approximation Theory, P. L. Butzer and J. Korevaar (Eds.), ISNM 5, Birkhäuser Verlag, Basel and Stuttgart, 1964, 109–129.