Vainikko, Eero, and Gennadi Vainikko. “Product Quasi-Interpolation in Logarithmically Singular Integral Equations”. Mathematical Modelling and Analysis 17, no. 5 (November 1, 2012): 696-714. Accessed November 25, 2024. https://jest.vgtu.lt/index.php/MMA/article/view/4904.