SONG, M.; WANG, S. Environmental Efficiency Evaluation of China Based on a Kind of Congestion and Undesirable Output Coefficient. Panoeconomicus, [S. l.], v. 62, n. 4, p. 453–468, 2015. DOI: 10.2298/PAN1504453S. Disponível em: https://panoeconomicus.org/index.php/jorunal/article/view/57. Acesso em: 3 may. 2024.