LAVRENYUK, S. P.; PTASHNIK, M. B. Pseudoparabolic variational inequalities without initial conditions. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 50, n. 7, p. 919–929, 1998. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/4872. Acesso em: 6 dec. 2025.