Phuong, N. T. D.; Huong, T. T. X. Effect of Natural Auxin from Portulaca Grandiflora Hook and Ipomoea Batatas (L.) Poir on the Formation Adventitious Roots in Vitro of Plumbago Zeylanica L. HCMCOUJS - Engineering and Technology 2018, 8, 30-37.