ZHELEZOVA, S. On the extension of a partial solution of d spreads to a parallelism. Mathematics and Education in Mathematics, [S. l.], v. 49, p. 173–177, 2020. Disponível em: https://smb.math.bas.bg/mem/index.php/memjournal/article/view/113. Acesso em: 5 oct. 2026.