PATRAKEEV, Mikhail. A Space with a Lusin $\pi$-Base Whose Square Has No Lusin $\pi$-Base. Topology Proceedings, [S. l.], v. 60, p. 17–30, 2021. Disponível em: https://www.topologyproceedings.org/index.php/tp/article/view/58. Acesso em: 30 jun. 2026.