Higuchi and Kuramoto, "Study of Possible Complex Formation Between Macromolecules and Certain Pharmaceuticals. II. Polyvinylpyrrolidone with p-Aminobenzoic Acid, Aminopyrine, Benzoic Acid, Salicylic Acid, p-Hydroxybenzoic Acid, m-Hydroxybenzoic Acid, Citric Acid, and Phenobarbital,", 1954

Higuchi and Kuramoto, "Study of Possible Complex Formation Between Macromolecules and Certain Pharmaceuticals. II. Polyvinylpyrrolidone with p-Aminobenzoic Acid, Aminopyrine, Benzoic Acid, Salicylic Acid, p-Hydroxybenzoic Acid, m-Hydroxybenzoic Acid, Citric Acid, and Phenobarbital,", 1954, Box: 11, Folder: 121. Personal papers of Takeru Higuchi, PP 359. University of Kansas. Kenneth Spencer Research Library. https://archives.lib.ku.edu/repositories/3/archival_objects/124755 Accessed December 24, 2025.