PTAK, Michał. Directions of changes in the functioning of economic instruments for environmental policy in Poland. Equilibrium. Quarterly Journal of Economics and Economic Policy, [S. l.], v. 5, n. 2, p. 129–140, 2010. DOI: 10.12775/EQUIL.2010.030. Disponível em: https://journals.economic-research.pl/eq/article/view/513. Acesso em: 18 may. 2024.