Delta Air Lines System Timetable 1981 September 8
MLA
Delta Air Lines, Inc.. "Delta Air Lines System Timetable 1981 September 8." Delta Flight Museum. 1981-09-08, https://dlg.galileo.usg.edu/do:delta_dal-tt_dal-tt-19810908.
APA
Delta Air Lines, Inc. (1981-09-08). Delta Air Lines System Timetable 1981 September 8. Retrieved from https://dlg.galileo.usg.edu/do:delta_dal-tt_dal-tt-19810908
Chicago
Delta Air Lines, Inc.. "Delta Air Lines System Timetable 1981 September 8." 1981-09-08. May 10, 2026. https://dlg.galileo.usg.edu/do:delta_dal-tt_dal-tt-19810908.
