APA (7th ed.) Citation

Geological Survey (U.S.), Griffith, G. E., Omernik, J. M., & Azevedo, S. (1998). Ecoregions of Tennessee. The Survey.

Chicago Style (17th ed.) Citation

Geological Survey (U.S.), Glenn E. Griffith, James M. Omernik, and Sandra Azevedo. Ecoregions of Tennessee. Reston, Va.: The Survey, 1998.

MLA (9th ed.) Citation

Geological Survey (U.S.), et al. Ecoregions of Tennessee. The Survey, 1998.