Our sources:
Enriquito D. de Guzman, Ricardo M. Umali, Emiliano D. Sotalbo. Guide to Philippine Flora and Fauna.
Madulid. Plants: Philippine Endangered Plants. Island Publishing House, Inc. 2000.
Elmer Merrill. An Enumeration of Philippine Plants, Volumes 1-4. Manila, Bureau of Printing).
Quisumbing. Medicinal Plants of the Philippines. Kather Publishing Co. Inc. 1978.