United States. Government Printing Office. (1931). Principles of design. GPO.
Chicago Style (17th ed.) CitationUnited States. Government Printing Office. Principles of Design. [Washington]: GPO, 1931.
MLA (9th ed.) CitationUnited States. Government Printing Office. Principles of Design. GPO, 1931.
Warning: These citations may not always be 100% accurate.