ANDREEV, K. N.; KHRUSLOV, E. Ya. Regularized integrals of motion for the Korteweg – de-Vries equation in the class of nondecreasing functions. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 67, n. 12, p. 1587–1601, 2015. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/2093. Acesso em: 5 dec. 2025.