1. Burkill, I. H. 1966.A Dictionary of Economic Products of the Malay Peninsula, 123Kuala Lumpur, Malaysia: Ministry of Agriculture & Co-operative.
2. Perry, L. M. 1980.Medicinal Plants of East and Southeast Asia, 436–444. Cambridge, MA, USA: MIT Press.
3. The essential oil of greater galanga (Alpinia galanga) from Malaysia