AVWIRI, G. Determination of radionuclide levels in soil and water around cement companies in Port Harcourt. Journal of Applied Sciences and Environmental Management, [S. l.], v. 9, n. 3, p. 26–29, 2006. DOI: 10.4314/jasem.v9i3.17348. Disponível em: https://www.ajol.info/index.php/jasem/article/view/17348. Acesso em: 25 sep. 2026.