Phenotyping of CYP 1A2 in Japanese population by analysis of caffeine urinary metabolites: absence of mutation prescribing the phenotype in the CYP 1A2 gene - Nakajima, M; Yokoi, T; Mizutani, M; Shin, S; Kadlubar, FF; Kamataki, T (Cancer Epidemiol Biomarkers Prev., 1994)