Amal K. Maji, Niladri Maity, Pratim Banerji, and Debdulal Banerjee. “Validated RP-HPLC-UV Method for the Determination of Betulin in Asteracantha Longifolia (L.) Nees. Extract”. International Journal of Phytomedicine, vol. 5, no. 2, June 2013, pp. 131-5, https://ijp.arjournals.org/index.php/ijp/article/view/241.