External assessment and institutional effects in Angolan higher education: national evidence from 877 programs. SciELO Preprints, 2026. DOI: 10.1590/SciELOPreprints.17384. Disponível em: https://preprints.scielo.org/index.php/scielo/preprint/view/17384. Acesso em: 20 ago. 2026.