NARVILKAR, D. K. A Solution of the Equations of Internal Ballistics of Guns Based on the lagrange density approximation. Defence Science Journal, [S. l.], v. 27, n. 4, p. 175–182, 2014. DOI: 10.14429/dsj.27.6702. Disponível em: https://publications.drdo.gov.in/ojs/index.php/dsj/article/view/6702. Acesso em: 16 jun. 2025.