Levy, John M. (virginia Polytechnic Institute And State University, Usa) (1) Levy, John M. (virginia Polytechnic Institute And State University, Hirt, Sonia A. (university Of Georgia, Dawkins, Casey J. (university Of Maryland (1) Guillebaud, John (university College London (1) Billingsley, John (1) Barker, Jeremiah (1)