1. Einige Eigenschaften Wilfscher Quadraturformeln;Eckhardt, Ulrich;Numer. Math.,1968
2. Best quadrature formulas and splines;Karlin, Samuel;J. Approximation Theory,1971
3. The fundamental theorem of algebra for monosplines satisfying certain boundary conditions and applications to optimal quadrature formulas;Karlin, Samuel,1969