kronrod_test, a C code which calls kronrod() to compute both a Gauss quadrature rule of order N, and the Gauss-Kronrod rule of order 2*N+1.
The computer code and data files described and made available on this web page are distributed under the MIT license
kronrod, a C code which can compute a Gauss and Gauss-Kronrod pair of quadrature rules of arbitrary order, by Robert Piessens, Maria Branders.