Higuchi et. al, "Inhibition of Hydrolysis of Esters in Solution by Formation of Complexes. IV. Stabilization of Benzocaine with 1-Ethyltheobromine,", 1957

Higuchi et. al, "Inhibition of Hydrolysis of Esters in Solution by Formation of Complexes. IV. Stabilization of Benzocaine with 1-Ethyltheobromine,", 1957, Box: 10, Folder: 169. Personal papers of Takeru Higuchi, PP 359. University of Kansas. Kenneth Spencer Research Library. https://archives.lib.ku.edu/repositories/3/archival_objects/124593 Accessed December 25, 2025.