XHAFERI, Besa. MEASURING PRODUCTIVITY. European Scientific Journal, ESJ, [S. l.], v. 8, n. 12, 2012. DOI: 10.19044/esj.2012.v8n12p%p. Disponível em: https://last.eujournal.org/index.php/esj/article/view/180. Acesso em: 4 jun. 2026.