RAMPAL, V. Unmanned Surveillance. Defence Science Journal, [S. l.], v. 51, n. 3, p. 215–216, 2002. DOI: 10.14429/dsj.51.2296. Disponível em: https://publications.drdo.gov.in/ojs/index.php/dsj/article/view/2296. Acesso em: 11 aug. 2025.