Higuchi et. al, "Sabadila Alkaloids. II. Alkaloidal Components of the Petroleum Ether Extract,", 1949, Box: 11, Folder: 90. Personal papers of Takeru Higuchi, PP 359. University of Kansas. Kenneth Spencer Research Library. https://archives.lib.ku.edu/repositories/3/archival_objects/124724 Accessed January 02, 2025.