Higuchi and Schroeter, "A Note on the Preparation of 1-(3,4-Dihydroxyphenyl)-2-methylamino-ethane Sulfonic Acid from Epinephrine,", 1960, Box: 11, Folder: 23. Personal papers of Takeru Higuchi, PP 359. University of Kansas. Kenneth Spencer Research Library. https://archives.lib.ku.edu/repositories/3/archival_objects/124657 Accessed May 18, 2024.