Helms, R. E. & MacPherson, R. E. Design and Preliminary Operation of the EgGCR Steam-Graphite Reaction Rate Experiment, report, June 1, 1964; (https://digital.library.unt.edu/ark:/67531/metadc869981/m1/1/: accessed October 21, 2018), University of North Texas Libraries, Digital Library, digital.library.unt.edu; .