Nyaga, Vasile. “Some General Questions of the Theory of Singular Operators in the Case of a Piecewise Lyapunov Contour”. Rev. Anal. Numér. Théor. Approx. 29, no. 1 (February 1, 2000): 57–73. Accessed April 27, 2024. https://ictp.acad.ro/jnaat/journal/article/view/2000-vol29-no1-art6.