Northwest Orient Airlines System Timetable 1979 April 30
MLA
Northwest Orient Airlines. "Northwest Orient Airlines System Timetable 1979 April 30." Delta Flight Museum. 1979-04-30, https://dlg.galileo.usg.edu/do:delta_nwa-tt_nwa-tt-19790430.
APA
Northwest Orient Airlines (1979-04-30). Northwest Orient Airlines System Timetable 1979 April 30. Retrieved from https://dlg.galileo.usg.edu/do:delta_nwa-tt_nwa-tt-19790430
Chicago
Northwest Orient Airlines. "Northwest Orient Airlines System Timetable 1979 April 30." 1979-04-30. September 18, 2026. https://dlg.galileo.usg.edu/do:delta_nwa-tt_nwa-tt-19790430.
