Higginbo R, Suschitzky H (1962). "Synthesis of Heterocyclic Compounds. 2. Cyclisation of O-Nitrophenyl Oxygen Ethers". J. Chem. Soc.: 2367–2370. DOI:10.1039/jr9620002367.
Olajos EJ, Salem H (2001). "Riot Control Agents: Pharmacology, Toxicology, Biochemistry and Chemistry". J Appl Toxicol. ج. 21 ع. 5: 355–391. DOI:10.1002/jat.767. PMID:11746179.