Goto, J; Hasegawa, K; Nambara, T; Iida, T (1992). “Studies on steroids. CCLIV. Gas chromatographic-mass spectrometric determination of 4- and 6-hydroxylated bile acids in human urine with negative ion chemical ionization detection”. Journal of Chromatography574 (1): 1–7. doi:10.1016/0378-4347(92)80091-4. PMID1629271.
Goto, J; Hasegawa, K; Nambara, T; Iida, T (1992). “Studies on steroids. CCLIV. Gas chromatographic-mass spectrometric determination of 4- and 6-hydroxylated bile acids in human urine with negative ion chemical ionization detection”. Journal of Chromatography574 (1): 1–7. doi:10.1016/0378-4347(92)80091-4. PMID1629271.