Images courtesy of Dr. Ricardo Bartelme (bartelme@umich.edu) under a Creative Commons license: BY-NC, except for the following:
Bergeson PS, et. al. Letter to the editor. Clinical Pediatrics. Feb 2000: 129-131. Figures 1 & 2.
Williams CP, et. al. Importance of identifying the inconspicuous penis: Prevention of circumcision complications. Urology. 2000; 56(1):140-143. Figures 1, 2, and 3.
Behrman RE, Vaughan III VC, editors. Nelson's Textbook of Pediatrics. p1393, photos A & B. Twelfth edition, 1983.