The Sale System and Its Use in Ukraine. Vallis Aurea, [S. l.], v. 4, n. 1, p. 101–109, 2018. DOI: 10.2507/IJVA.4.1.8.50. Disponível em: https://ojs.srce.hr/index.php/vallisaurea/article/view/26444. Acesso em: 25 aug. 2025.