1. United States Pharmacopeia XIX, p 419
2. Toeplitz, B., Squibb Institute, personal communication
3. Puar, M., Squibb Institute, personal communication
4. Whigan, D., Squibb Institute, unpublished observation
5. Identification of Drugs and Other Toxic Compounds from Their Ultraviolet Spectra. Part I: Ultraviolet Absorption Properties of Sixteen Structural Groups