BLACKMORE, D.; PRYKARPATSKY, A. K.; PRYKARPATSKY, Ya. A.; SAMOILENKO, A. M. Theory of multidimensional Delsarte – Lions transmutation operators. I. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 70, n. 12, p. 1660–1695, 2018. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/1667. Acesso em: 27 apr. 2025.