求助sciencedirect文献几篇，谢谢！

Environmental energy efficiency of China's regional economies: A non-oriented slacks-based measure analysis[size=0.92em] Original Research Article
The Social Science Journal, In Press, Corrected Proof, Available online 7 February 2013
Ning Zhang, Yongrok Choi





Technical efficiency of economic systems of EU-15 countries based on energy consumption[size=0.92em] Original Research Article
Energy Policy, Volume 55, April 2013, Pages 426-434
Christina Bampatsou, Savas Papadopoulos, Efthimios Zervas




Energy efficiency and productivity change of China’s iron and steel industry: Accounting for undesirable outputs[size=0.92em] Original Research Article
Energy Policy, Volume 54, March 2013, Pages 204-213
Feng He, Qingzhi Zhang, Jiasu Lei, Weihui Fu, Xiaoning Xu




Greenhouse gas emissions and the technical efficiency of dairy farmers[size=0.92em] Original Research Article
Ecological Indicators, Volume 29, June 2013, Pages 478-488
O.K. Shortall, A.P. Barnes

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