1. Product Focus, Chemical Week 10 (1999) 47.
2. Ullmanns Encyclopedia of Industrial Chemistry, 6th Edition, 1998, electronic release.
3. New Reactions in Various Fields and Production of Specialty Chemicals
4. The Use of Zeolite Catalysts for the Synthesis of Nitrogen-Containing Organic Intermediates
5. W.F. Hölderich, in: G. Alberti, T. Bein (Eds.), Comprehensive Supramolecular Chemistry, Vol. 7, Pergamon Press, New York, 1996, p. 671.