APA (7th ed.) Citation

Illinois State Geological Survey. Petroleum industry in Illinois. Illinois State Geological Survey.

Chicago Style (17th ed.) Citation

Illinois State Geological Survey. Petroleum Industry in Illinois. Urbana, IL: Illinois State Geological Survey.

MLA (9th ed.) Citation

Illinois State Geological Survey. Petroleum Industry in Illinois. Illinois State Geological Survey.

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