1. 1. S. An, X. Hu, and J. Wang, “Urban taxis and air pollution: a case study in Harbin, China,” J. Transp. Geogr., 2011, doi: 10.1016/j.jtrangeo.2010.12.005.
   2. H. Herrmann and H. Bucksch, “geoinformation,” in Dictionary Geotechnical Engineering/Wörterbuch GeoTechnik, 2014.
   3. C. R. Dow, D. B. Nguyen, S. C. Wang, S. F. Hwang, and M. F. Tsai, “A Geo-Aware Taxi Carrying Management System by Using Location Based Services and Zone Queuing Techniques on Internet of Things,” Mob. Inf. Syst., 2016, doi: 10.1155/2016/9817374.
   4. J. Hospodka, “Cost-benefit analysis of electric taxi systems for aircraft,” J. Air Transp. Manag., 2014, doi: 10.1016/j.jairtraman.2014.05.002.
   5. T. Krstić Simić and O. Babić, “Airport traffic complexity and environment efficiency metrics for evaluation of ATM measures,” J. Air Transp. Manag., 2015, doi: 10.1016/j.jairtraman.2014.11.008.