YAHAYA, Jibrin Danjuma; ALFA, Abraham Ayegba; RAJI, Muhammed; ABDULSALAMI, Momohjimoh. Unsteady Darcy-Brinkman Axial Flow in a Porous Concentric Annulus: A Semi-Analytical Riemann-Sum Approach. FUDMA JOURNAL OF SCIENCES, [S. l.], v. 10, n. 10, p. 269–275, 2026. DOI: 10.33003/fjs-2026-1010-5506. Disponível em: https://fjs.fudutsinma.edu.ng/index.php/fjs/article/view/5506. Acesso em: 14 jul. 2026.