HEMBARS'KA, S. B. Tangential limit values of a biharmonic poisson integral in a disk. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 49, n. 9, p. 1171–1176, 1997. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/5114. Acesso em: 5 dec. 2025.