Fu KI, Kato S, Sano Y, Onuma EK, Saito Y, Matsuda T, Koba I, Yoshida S, Fujii I, Staging of Early Colorectal Cancers : Magnifying Colonoscopy versus Endoscopic Ultrasonography for Estimation of Depth of Invasion, Dig Dis Sci. 2008 Jul;53(7):1886-92. Epub 2007 Dec 13. PMID: 18080834 [PubMed – indexed for MEDLINE]