Higuchi and Zuck, "Investigation of Complexes Formed in Solution by Caffeine. III. Interactions Between Caffeine and Aspirin, pHydroxybenzoic Acid, m-Hydroxybenzoic Acid, Salicylic Acid, Salicylate Ion, and Butyl Paraben", 1953

Higuchi and Zuck, "Investigation of Complexes Formed in Solution by Caffeine. III. Interactions Between Caffeine and Aspirin, pHydroxybenzoic Acid, m-Hydroxybenzoic Acid, Salicylic Acid, Salicylate Ion, and Butyl Paraben", 1953, Box: 10, Folder: 187. Personal papers of Takeru Higuchi, PP 359. University of Kansas. Kenneth Spencer Research Library. https://archives.lib.ku.edu/repositories/3/archival_objects/124611 Accessed February 16, 2026.