APA-referens (7:e uppl.)

CLARK II, E. H., HAVERKAMP, J. A., & CHAPMAN, W. (1985). Eroding soils: The off-farm impacts. Th Conservation Foundation.

Chicago-referens (17:e uppl.)

CLARK II, Edwin H., Jenniver A. HAVERKAMP, och William CHAPMAN. Eroding Soils: The Off-farm Impacts. Washington: Th Conservation Foundation, 1985.

MLA-referens (9:e uppl.)

CLARK II, Edwin H., et al. Eroding Soils: The Off-farm Impacts. Th Conservation Foundation, 1985.