MEL'NICHENKO, I. P.; PLAKSA, S. A. Reduction of the principal biharmonic problem for a quadrant to nonsingular integral equations. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 47, n. 6, p. 775–784, 1995. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/5471. Acesso em: 14 apr. 2025.