Yusuf, Debby Putri Mutiara, et al. “Skrining Fitokimia Dan Uji Aktivitas Antioksidan Ekstrak Etanol Propolis Lebah Kelulut (Heterotrigona itama): Phytochemical Screening and Antioxidant Activity Test of Kelulut Bee Propolis (Heterotrigona Itama) Ethanol Extract”. Proceeding of Mulawarman Pharmaceuticals Conferences, vol. 14, no. 1, Dec. 2021, pp. 237-41, doi:10.25026/mpc.v14i1.549.