"Past CDC Directors/Administrators". Office of Enterprise Communication. Centers for Disease Control and Prevention (U.S. Department of Health and Human Services). February 19, 2009. Diarsipkan dari versi aslinya tanggal May 6, 2009. Diakses tanggal May 19, 2009.
"Past CDC Directors/Administrators". Office of Enterprise Communication. Centers for Disease Control and Prevention (U.S. Department of Health and Human Services). February 19, 2009. Diarsipkan dari versi aslinya tanggal May 6, 2009. Diakses tanggal May 19, 2009.