BALAN, V.A. Construction of radially bounded antiproximinal sets in $L_1$. Carpathian Mathematical Publications, [S. l.], v. 2, n. 2, p. 4–9, 2010. Disponível em: https://journals.pnu.edu.ua/index.php/cmp/article/view/3961. Acesso em: 5 may. 2024.