JASHARI, Hasan. Primary and Secondary Data in Doctoral Research Studies. European Journal of Social Science Education and Research, London, U.K., v. 11, n. 4, p. 57–65, 2024. DOI: 10.26417/tg48kv85. Disponível em: https://revistia.com/index.php/ejser/article/view/68. Acesso em: 1 apr. 2025.