Clinical and epidemiological studies on 252 cases of acute hepatitis A during the past 15 years - WASADA, Mitsuru; SIRAISHI, Koichi; NAKANO, Atsushi; NISHIZAKI, Yasuhiro; UCHIYAMA, Junzo; ITAKURA, Masaru; MATSUZAKI, Shohei; WATANABE, Norihito; KOBAYASHI, Fuminori; NAGATA, Naruhiko; OKAZAKI, Yuhaku; KAGAWA, Tatehiro (Kanzo, 1996)