1. Wawzonek , S. 1975. Heterocyclic Compounds, Vol. 2, 173New York: John Wiley and Sons.
2. Dean , F. M. 1963. Naturally Occurring Oxygen Ring Compounds, 176London: Butterworths.
3. Livingstone , R. 1996. Rod's Chemistry of Carbon Compounds,, 2nd ed., 4Amsterdam: Elsevier.
4. Kartritzkey , A. R. and
Rees , C. W. , eds. 1984. Comprehensive Heterocyclic Chemistry, 3Oxford: Pergamon Press.
5. Starnton , J. 1979. Comprehensive Organic Chemistry, Edited by:
Barton , D. M. R. and
Ollis , W. D. Vol. 4, 629Oxford: Pergamon Press.