1. T. Eicher and S.Hauptmann , The Chemistry of Heterocycles: Structure, Reactions, Syntheses, and Applications , Wiley-VCH , Weinheim , 2nd edn, 2003
2. Modern Heterocyclic Chemistry , ed. J. Alvarez-Builla , J. J. Vaquero and J. Barluenga , Wiley-VCH Verlag GmbH , Weinheim , 2011
3. J. A. Joule and K.Mills , Heterocyclic Chemistry , Wiley-Blackwell , Oxford , 2010
4. S. P. Nolan , N-Heterocyclic Carbenes in Synthesis , Wiley-VCH , Weinheim , 2006 , pp. 1–304
5. Asymmetric Synthesis of Nitrogen Heterocycles , ed. J. Royer , Wiley-VCH , Weinheim , 2009