A Prospective Comparison of Performance of Biopsy Forceps Used in Single Passage with Multiple Bites During Upper Endoscopy - Chu , K M; Yuen , S T; Wong , W M; Wong , K W; Lai , K C; Hu , W H C; Leung , S Y; Yuen , M F; Lam , S K; Wong , B C Y (Endoscopy, 2003)