*Northwest Airlines Schedule 1938 October 1
MLA
Northwest Airlines. "*Northwest Airlines Schedule 1938 October 1." Delta Flight Museum. 1938-10-01, https://dlg.galileo.usg.edu/do:delta_nwa-tt_nwa-tt-19381001.
APA
Northwest Airlines (1938-10-01). *Northwest Airlines Schedule 1938 October 1. Retrieved from https://dlg.galileo.usg.edu/do:delta_nwa-tt_nwa-tt-19381001
Chicago
Northwest Airlines. "*Northwest Airlines Schedule 1938 October 1." 1938-10-01. June 17, 2025. https://dlg.galileo.usg.edu/do:delta_nwa-tt_nwa-tt-19381001.
