“Isolation and Elucidation Structure of 28-Hydroxy-3-Friedelanone of Nyamplung (Callophyllum inophyllum, Linn.) Leaves”, J. Pure App. Chem. Res., vol. 9, no. 2, pp. 117–125, Aug. 2020, doi: 10.21776/ub.jpacr.2020.009.02.518.