M. ALKAWAZ, S. Estimate The Effect Of International Trade For Invironmental Services Sample From WTO Countries. TANMIYAT AL-RAFIDAIN, [S. l.], v. 37, n. 120, p. 9–28, 2018. DOI: 10.33899/tanra.2018.159988. Disponível em: https://tanmiyat.uomosul.edu.iq/index.php/tanmiyat/article/view/29868. Acesso em: 8 sep. 2025.