Biggs, D. C., Bol, M. A., & Baker, J. (2009). Guidebook for Conducting Airport User Surveys. Transportation Research Board.
Chicago-viite (17. p.)Biggs, D. C., M. A. Bol, ja J. Baker. Guidebook for Conducting Airport User Surveys. Washington, D.C.: Transportation Research Board, 2009.
MLA-viite (9. p.)Biggs, D. C., et al. Guidebook for Conducting Airport User Surveys. Transportation Research Board, 2009.
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