On existence of invariant tori for countable systems of differential-difference equations defined on infinite-dimensional tori. Neliniini Kolyvannya, [S. l.], v. 12, n. 3, p. 347–367, 2009. Disponível em: https://twinhead.imath.kiev.ua/index.php/nosc/article/view/531. Acesso em: 21 jan. 2026.