INVESTIGATION OF QUALITY OF SERVICE (QoS) OF GSM NETWORK PROVIDERS AT FEDERAL UNIVERSITY, GUSAU, ZAMFARA STATE. Nigerian Journal of Physics, [S. l.], v. 30, n. 2, p. 78–85, 2021. Disponível em: https://njp.nipngr.org/index.php/njp/article/view/97. Acesso em: 19 may. 2025.