1. P. J. Davis and P. Rabinowitz,Numerical Integration, Blaisdell Publishing Company, Waltham, Mass. (1967).
2. V. I. Krylov,Approximate Calculation of Integrals, translated by A. H. Stroud, The Macmillan Company, New York (1962).
3. I. Stakgold,Boundary Value Problems of Mathematical Physics, Vol. 1, The Macmillan Company, New York (1967).
4. G. W. Struble,Orthogonal polynomials: variable-signed weight functions, Numerische Mathematik, 5 (1963), pp. 88–94.
5. E. Isaacson and H. B. Keller,Analysis of Numerical Methods, John Wiley and Sons, New York (1966).