1. Dean, F. M. 1963. “Naturally Occurring Oxygen Ring Compounds”. London: Butterworth.
2. Murray, R. D.H., Mendez, J. and Brown, S. A. 1982. “The Natural Coumarins: Occurrence, Chemistry and Biochemistry”. New York: Wiley.
3. Meuly, W. C. 1979. “Kirk‐Othmer, Encyclopedia of Chemical Technology”. Vol. 17, 196New York: John Wiley and Sons. 3rd Ed
4. Stuart, D. M. and Hruschka, J. K.IbidVol. 16, 951–955.
5. Taylor, W. I., Chant, B. and Van Loveren, G.IbidVol. 4, 15