Vince, Susan W.; Humphrey, Stephen R.; Simmons, Robert W. (September 1989). The Ecology of Hrdric Hammocks(PDF). Biological Report. Washington, D.C.: U.S. Department of the Interior Fish and Wildlife Service. p. 4. Retrieved December 12, 2018.
Vince, Susan W.; Humphrey, Stephen R.; Simmons, Robert W. (September 1989). The Ecology of Hrdric Hammocks(PDF). Biological Report. Washington, D.C.: U.S. Department of the Interior Fish and Wildlife Service. pp. 1–3. Retrieved December 12, 2018.