PERIKA MOUNIKA, et al. “Quantitative Estimation of Atorvastatin Calcium in Bulk and Tablet Dosage Forms Using FTIR Spectroscopy”. International Journal of Pharma and Bio Sciences, vol. 9, no. 2, June 2018, pp. 221-32, doi:10.22376/ijpbs.2018.9.2.p221-232.