LIU, Qing, and Qiwei QIAN. “Research on the Efficiency of Major Airports in China’s Six Major Airport Cluster: Based on Common Frontier Super-Efficiency DEA and Malmquist Method”. Promet - Traffic&Transportation, vol. 36, no. 5, Oct. 2024, pp. 885-01, doi:10.7307/ptt.v36i5.609.