OUDE LANSINK, A.; WALL, A. Frontier models for evaluating environmental efficiency: an overview. Economics and Business Letters, [S. l.], v. 3, n. 1, p. 43–50, 2014. DOI: 10.17811/ebl.3.1.2014.43-50. Disponível em: https://reunido.uniovi.es/index.php/EBL/article/view/10253. Acesso em: 29 mar. 2024.