Amphibians and Reptiles in Duval County - Texas Cooperative Wildlife Collection list of species found in the county. wfscnet.tamu.edu/tcwc/checklist/DUVAL066.HTM
Butterflies of Duval County, Texas - Information about and pictures of all the known species of butterflies in the county. www.npwrc.usgs.gov/resource/DISTR/LEPID/BFLYUSA/chklist/states/counties/tx_131.htm
Duval County QuickFacts from the US Census Bureau - Population, demographic, and housing information from the 1990 census. Link to Tiger map of the county. quickfacts.census.gov/cgi-bin/county?cnty=48131
Handbook of Texas Online : Duval County - Current and historical information about Duval County. www.tsha.utexas.edu/handbook/online/articles/view/DD/hcd11.html
