"scientific article published on 26 July 2002"@en . "ISOLATION OF ALKALOIDS FROM GOLDENSEAL (HYDRASTIS CANADENSIS RHIZOMES) USING pH-ZONE REFINING COUNTERCURRENT CHROMATOGRAPHY"@en . . . "ISOLATION OF ALKALOIDS FROM GOLDENSEAL (HYDRASTIS CANADENSIS RHIZOMES) USING pH-ZONE REFINING COUNTERCURRENT CHROMATOGRAPHY"@en . "ISOLATION OF ALKALOIDS FROM GOLDENSEAL (HYDRASTIS CANADENSIS RHIZOMES) USING pH-ZONE REFINING COUNTERCURRENT CHROMATOGRAPHY"@en .