Gillham, T.; Cerveny, B. & Turek, E. West Hackberry Tertiary Project. Quarterly technical progress report, March 3, 1995--June 2, 1995, report, May 31, 1995; (https://digital.library.unt.edu/ark:/67531/metadc784816/m1/1/: accessed April 20, 2019), University of North Texas Libraries, Digital Library, digital.library.unt.edu; .