References
- The diabetes market. Executive Summary, Frost and Sullivan March, 1977; 34–45
- Feigl F. Spot Tests in Organic Analysis, 6th ed. Elsevier. 1960
- Dole V. P., Kim N. K., Eglitis I. Detection of narcotic drugs, tranquilizers, amphetamines and barbiturates in urine. J. Am. Med. Assoc October 24, 1966; 198(4)
- Friedenberg R. U.S. Patent. 3,915,639, October 28, 1975, Drug abuse Dipstick
- Friedenberg R., Gibson J. Diagnostic indicator, method of preparation and use thereof, Patent Pending
- Friedenberg R. Drug abuse testing. Clin. Lab. Prod. News April, 1977
- Vidie E. Detection Methods for Narcotics and Drugs in Body Fluids, Sueht Missbrauch, 2. Voellig Neu Bearbeitete Aufl. 1975; 64–75