APA (7th ed.) Citation

United States. Bureau of Entomology. (1921). Map showing spread of Mexican cotton boll weevil from 1892 to 1920. [publisher not identified].

Chicago Style (17th ed.) Citation

United States. Bureau of Entomology. Map Showing Spread of Mexican Cotton Boll Weevil from 1892 to 1920. [Washington]: [publisher not identified], 1921.

MLA (9th ed.) Citation

United States. Bureau of Entomology. Map Showing Spread of Mexican Cotton Boll Weevil from 1892 to 1920. [publisher not identified], 1921.

Warning: These citations may not always be 100% accurate.