KELLMAN, Mitchell H.; SHACHMUROVE, Yochanan. Evolving sophistication of trade patterns in a transition economy - machinery exports of Poland 1980-2009. Economics and Business Review, Poland, v. 12, n. 3, p. 9–41, 2012. DOI: 10.18559/ebr.2012.3.849. Disponível em: https://journals.ue.poznan.pl/ebr/article/view/849. Acesso em: 3 apr. 2025.