Katani, R., and S. Shahmorad. “The Block by Block Method With Romberg Quadrature for Solving Nonlinear Volterra Integral Equations on the Large Intervals”. Ukrains’kyi Matematychnyi Zhurnal, Vol. 64, no. 7, July 2012, pp. 919-31, https://umj.imath.kiev.ua/index.php/umj/article/view/2628.