RT Journal Article SR Electronic T1 Complexity and the hepatitis viruses. JF Gut JO Gut FD BMJ Publishing Group Ltd and British Society of Gastroenterology SP 1770 OP 1771 DO 10.1136/gut.35.12.1770 VO 35 IS 12 A1 B S Blumberg YR 1994 UL http://gut.bmj.com/content/35/12/1770.abstract AB