Wallis, R. (2003). How safe are our skies?: Assessing the airlines' response to terrorism. Praeger.
Chicago-viite (17. p.)Wallis, Rodney. How Safe Are Our Skies?: Assessing the Airlines' Response to Terrorism. Westport, Conn.: Praeger, 2003.
MLA-viite (9. p.)Wallis, Rodney. How Safe Are Our Skies?: Assessing the Airlines' Response to Terrorism. Praeger, 2003.
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