Composition #4: KNAPP, JE., HUSSEIN, FT., BEAL, JL., DOSKOTCH, RW., TOMIMATSU, T. ISOLATION OF 2 BISBENZYLISOQUINOLINE ALKALOIDS FROM RHIZOMES AND ROOTS OF XANTHORHIZA SIMPLICISSIMA . journal of pharmaceutical sciences, 1967, vol. 56, no. 1, p. 139–+. DOI: 10.1002/jps.2600560129.
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