DALETSKY , A. Yu.; PODKOLZIN , G. B. Group approach to integration of the Todes infinite chain. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 40, n. 4, p. 518–521, 1988. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/9190. Acesso em: 6 dec. 2025.