ONYECHI, N.I ,. CERTIFICATION AND DIPLOMA COURSES IN LIBRARY AND INFORMATION SCIENCE IN NIGERIA- STATE OF THE ART. NigerBiblios: Journal of National Library of Nigeria, [S. l.], v. 12, n. 1, p. 15–19, 2025. Disponível em: https://nigerbiblios.nln.gov.ng/index.php/nigerbiblios/article/view/405. Acesso em: 10 sep. 2025.