AL-BAKRI, Nadia F; HASHIM, Soukaena Hassan. Reducing Data Sparsity in Recommender Systems. Al-Nahrain Journal of Science, [S. l.], v. 21, n. 2, p. 138–147, 2018. Disponível em: https://mail.anjs.edu.iq/index.php/anjs/article/view/1736. Acesso em: 22 may. 2026.