Johnson Gavin, Hatfield Adrian, Webster George, Groves Chris, Rodriguez-Justo Manuel
Department of Gastroenterology and University College Hospital, London, United Kingdom.
Gastrointest Endosc. 2010 Mar;71(3):622-3; discussion 623. doi: 10.1016/j.gie.2009.10.014. Epub 2009 Dec 9.