APA (7th ed.) Citation

Illinois State Geological Survey. (1931). Information circular. The Survey.

Chicago Style (17th ed.) Citation

Illinois State Geological Survey. Information Circular. Urbana, Ill.: The Survey, 1931.

MLA (9th ed.) Citation

Illinois State Geological Survey. Information Circular. The Survey, 1931.

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