KOLBA, Paweł M.; KOTKOWSKI, Radosław. Business Cycles Indicators and Short-term Forecasts of Polish Industry Production Index. Oeconomia Copernicana, [S. l.], v. 4, n. 3, p. 65–79, 2013. DOI: 10.12775/OeC.2013.023. Disponível em: https://oeconomia.pl/index.php/oc/article/view/431. Acesso em: 8 feb. 2026.