1. K. F. Rabe, S. Hurd, and A. Anzueto, Am. J. Respir. Crit. Care Med., 176(6), 532 – 535 (2007).
2. British Pharmacopoeia (BP), The Stationary Office on Behalf of Medicines and Healthcare Products Regulatory Agency, London, UK (2016).
3. S. C. Sweetman, Martindale: The Complete Drug Reference, 40th Edn., Pharmaceutical Press: London (2016).
4. H. M. Ahmed and B. J. Clark, J. Ion Exchange, 18, 402 – 405 (2007).
5. A. S. Nevse, S. Yadav, R. N. Purohit, et al., World J. Pharm. Sci., 5, 795 – 802 (2016).