RontoN., and PutyatinaT. “Application of the Collocation Method to the Multi-Point Boundary Value Problems With Integral Boundary Conditions ”. Ukrains’kyi Matematychnyi Zhurnal, Vol. 44, no. 11, Nov. 1992, pp. 1548-55, https://umj.imath.kiev.ua/index.php/umj/article/view/8258.