MARKOVSKY , A. I. Remarks about Lp — Lq estimates for solutions of the Klein — Gordon equations. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 44, n. 2, p. 233–245, 1992. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/7837. Acesso em: 6 dec. 2025.