Li, Cheng, Qing-Hong Hao, Hai-Yan Liu, Chun Wang, Jing-Jun Ma, and Wen-Gang Zhu. 2013. “[HSO3-pmim][CH3SO3] As an Efficient Catalyst for the Synthesis of 1,5-Benzodiazepine Derivatives under Ultrasound Irradiation”. Asian Journal of Chemistry 25 (11):6243-46. https://doi.org/10.14233/ajchem.2013.14340.