Economic situational diagnosis of commercial activity Tulcán - Carchi, period 2018. Business Vision, [S. l.], n. 9, p. 240–251, 2019. DOI: 10.32645/13906852.886. Disponível em: https://revistasdigitales.upec.edu.ec/index.php/visionempresarial/article/view/886. Acesso em: 21 oct. 2026.