APA (7th ed.) Citation

Bergstrom, R. E., Piskin, K., & Follmer, L. R. (1976). Geology for planning in the Springfield-Decatur region, Illinois. Illinois State Geological Survey.

Chicago Style (17th ed.) Citation

Bergstrom, Robert Edward, Kemal Piskin, and Leon R. Follmer. Geology for Planning in the Springfield-Decatur Region, Illinois. Urbana: Illinois State Geological Survey, 1976.

MLA (9th ed.) Citation

Bergstrom, Robert Edward, et al. Geology for Planning in the Springfield-Decatur Region, Illinois. Illinois State Geological Survey, 1976.