ALFA, B.; ALIYU, S. I.; ADAMU, Y.; TSEPAV, M. T. Motion of Photons in a Gravitational Field of Massive Body. Nigerian Journal of Physics, [S. l.], v. 33, n. 4, p. 100–108, 2024. DOI: 10.62292/njp.v33i4.2024.315. Disponível em: https://njp.nipngr.org/index.php/njp/article/view/315. Acesso em: 3 apr. 2025.