BROLL, Udo; JAUER, Julia. International trade in differentiated goods, financial crisis and the gravity equation. Economics and Business Review, Poland, v. 1, n. 2, p. 76–94, 2015. DOI: 10.18559/ebr.2015.2.4. Disponível em: https://journals.ue.poznan.pl/ebr/article/view/209. Acesso em: 3 apr. 2025.