Kuznetsova О. M. Continuation of positively determined functions on the ball in the infinite sphere . Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 44, n. 4, p. 489–497, 1992. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/7890. Acesso em: 6 dec. 2025.