Key, M H; Stephens, R B; Koch, J & Pennington, D. X-ray imaging to characterize MeV electronics propagation through plastic targets, article, September 3, 1999; (https://digital.library.unt.edu/ark:/67531/metadc623302/m1/1/: accessed August 14, 2018), University of North Texas Libraries, Digital Library, digital.library.unt.edu; .