1. The United States Pharmacopeia 27, The National Formulary 22, United States Pharmacopeial Convention, INC., 2004, pp. 678–682.
2. British Pharmacopoeia, The Stationery Office, London, 2001, p. 599.
3. On the analysis of diprophylline;Abu-Shady;Egypt J. Pharm. Sci.,1987
4. Spectrophotometric determination of some theophylline derivatives;Nikolic;Acta Pharm. Jugosl.,1988
5. Application of second-derivative spectrophotometry to the determination of bromhexine hydrochloride and UV spectrophotometry to the determination of diprophylline in compound preparations;Tang;Yaoxue Xuebao,1986