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 64, no. 7 (July 25, 2012): 919-931. Accessed April 23, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/2628.