OKPALA, A. O. Knowledge Infrastructure, Service Sector, And Economic Growth In Africa. International Business & Economics Research Journal (IBER), [S. l.], v. 6, n. 7, 2007. DOI: 10.19030/iber.v6i7.3388. Disponível em: https://clutejournals.com/index.php/IBER/article/view/3388. Acesso em: 17 jul. 2024.