1. H. Neunhoeffer, P.F. Wiley, in Chemistry of 1,2,3-Triazines and 1,2,4-Triazines, Tetrazines and Pentazines, ed. by A. Weissberger, E.C. Taylor, (John Wiley and Sons, New York, Chichester, Brisbane, Toronto, 1978), pp. 1001–1004
2. H. Neunhoeffer, in Comprehensive Heterocyclic Chemistry, vol. 3, eds. by A.R. Katritzky, C.W. Rees (Pergamon Press, Oxford, 1984), pp. 385–456
3. M.A. Ali, S.E. Livingstone, Coord. Chem. Rev. 13, 101–132 (1974)
4. R.M. Abdel-Rahman, Pharmazie 56, 275–286 (2001)
5. R.M. Abdel-Rahman, J.M. Morsy, S. El Edfawy, H.A. Amine, Pharmazie 54, 667–671 (1999)