University, U. c. S. L. (1940). Chief Flight Instructor George Gruen of Parks College.
Chicago Style (17th ed.) CitationUniversity, Unknown creator; St. Louis. Chief Flight Instructor George Gruen of Parks College. 1940.
MLA (8th ed.) CitationUniversity, Unknown creator; St. Louis. Chief Flight Instructor George Gruen of Parks College. 1940.
Warning: These citations may not always be 100% accurate.