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3. Trivedi, B.C., A.J. Digioia, and P.J. Menardi, JAOCS 58:754 (1981).
4. Takano, S., and K. Tsuji, JAOCS 60:870 (1983).
5. Harnsberger, B.G., and J.L. Riebsomer, J. Heterocyclic Chem. 1:188(1964).