WILLIAMS, H. Some engineering problems. Defence Science Journal, [S. l.], v. 2, n. 2-3, p. 95–97, 2013. DOI: 10.14429/dsj.2.3370. Disponível em: https://publications.drdo.gov.in/ojs/index.php/dsj/article/view/3370. Acesso em: 17 jun. 2025.