En, Le Hong, et al. “Evaluation of Plant Growth Regulators on Root Formation of Semihardwood and Hardwood Cuttings of Sarcandra Glabra (Thunb.) Nakai”. Academia Journal of Biology, vol. 38, no. 3, Sept. 2016, pp. 359-66, doi:10.15625/0866-7160/v38n3.7843.