RASSIAS, J. M. Multi-Dimensional Landau Extremum Problems. The Journal of the Indian Mathematical Society, [S. l.], v. 66, n. 1-4, p. 11–16, 1999. Disponível em: http://informaticsjournals.com/index.php/jims/article/view/21908. Acesso em: 4 may. 2024.