Ferguson, R. B. Preliminary Raw Data Release: Greenville 1° x 2° NTMS Area, Georgia, North Carolina, and South Carolina, report, March 1978; (https://digital.library.unt.edu/ark:/67531/metadc784645/m1/1/: accessed April 22, 2019), University of North Texas Libraries, Digital Library, digital.library.unt.edu; .