CHINESE JOURNAL OF EPIDEMIOLOGY, Volume 29, Issue 8,2008, Pages 775-778,
CHINESE JOURNAL OF EPIDEMIOLOGY, Volume 29, Issue 8,2008, Pages 843-844,
CHINESE JOURNAL OF EPIDEMIOLOGY, Volume 29, Issue 8,2008, Pages 846-847,
CHINESE JOURNAL OF EPIDEMIOLOGY, Volume 29, Issue 8,2008, Pages 810-814,