Baes, Charles F., Jr.; Schreyer, J. M. & Lesser, J. M. The Chemistry of Uranium(VI) Orthophosphate Solutions, report, June 22, 1953; (https://digital.library.unt.edu/ark:/67531/metadc172809/m1/1/: accessed April 21, 2019), University of North Texas Libraries, Digital Library, digital.library.unt.edu; .