Kaderkar, Dattatray, et al. “Difference Spectrophotometric Method for Estimation of Amitriptyline Hydrochloride in Bulk Drug”. Journal of Drug Delivery and Therapeutics, vol. 9, no. 4-A, Sept. 2019, pp. 301-4, https://doi.org/10.22270/jddt.v9i4-A.3475.