Prabu, S. Lakshmana, et al. “Development and Validation of Stability-Indicating RP-HPLC Method for Coumarin Assay in Bulk Drugs and Pharmaceutical Products”. International Journal of Pharmaceutical Sciences and Nanotechnology(IJPSN), vol. 6, no. 3, Nov. 2013, pp. 2187-92, doi:10.37285/ijpsn.2013.6.3.11.