DYMARSKII, Ya. M. On manifolds of eigenfunctions and potentials generated by a family of periodic boundary-value problems. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 48, n. 6, p. 771–781, 1996. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/5277. Acesso em: 5 dec. 2025.