Khan, M. A., and S. Rashid. “Selective Nitrations of 2-(1’-Phenylpyrazol-4’-Yl) Benzimidazoles: Nitrations of Pyrazoles”. Biological Sciences - PJSIR, vol. 52, no. 6, Dec. 2009, pp. 289-92, http://v2.pjsir.org/index.php/biological-sciences/article/view/568.