Bowen, J. (2010). The economic geography of air transportation: Space, time, and the freedom of the sky. Routledge.
Chicago-viite (17. p.)Bowen, John. The Economic Geography of Air Transportation: Space, Time, and the Freedom of the Sky. London: Routledge, 2010.
MLA-viite (9. p.)Bowen, John. The Economic Geography of Air Transportation: Space, Time, and the Freedom of the Sky. Routledge, 2010.
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