1. H. B. Gray , J. G.Swanson and T. H.Crawford, Project Acac: An Experimental Investigation in Synthesis and Structure, Bodgen and Quigley, New York, 1972
2. R. C. Mehrotra , R.Bohra and D. P.Gaur, Metal β-Diketonates and Allied Derivatives, Academic Press, London, 1978
3. Chemistry of metal β-diketonates
4. 698. cycloButadiene and some other pseudoaromatic compounds
5. F. A. Cotton and G.Wilkinson, Advanced Inorganic Chemistry, John Wiley & Sons, New York, 5th edn, 1988