1. Eisner, U. and Kuthan, J., Chem. Rev., 1972, vol. 72, p.1.
2. Stout, D. and Meyers, A., Chem. Rev., 1982, vol. 82, p.223.
3. Lavilla, R., Chem. Soc., Perkin Trans. 1, 2002, p. 1142.
4. Lounasmaa, M. and Tolvanen, A., Compr. Heterocyclic Chem. II, 1996, vol. 5, p.135.
5. Balasubramanian, M. and Keay, J.G., Compr. Heterocyclic Chem. II, 1996, vol. 5, p.245.