1. Shelef, M.: Selective Catalytic Reduction of NOx with N-Free Reductants. Chem. Rev. 95 (1995), 209–225
2. Wahl, T.; Jacob, E.; Weisweiler, W.: NOx-Verminderung bei Dieselmotoren, Teil 1: Modellgasuntersuchungen mit stickstofffreien Reduktionsmitteln. MTZ 57 (1996), 506–514
3. Bosch, H.; Janssen, F.: Catalytic Reduction of Nitrogen Oxides. Catal. Today, 2 (1988), 369–532
4. Koebel, M.; Elsener, M.; Marti, T.: NOx-Reduction in Diesel Exhaust Gas with Urea and Selective Catalytic Reduction. Combust. Sci. and Tech. Vol. 121 (1996), 85–102
5. Takahashi, N. et al: the new concept 3-way catalyst for automotive lean-burn engine: NOx storage and reduction catalyst. Proc. 1st World Congress on Environmental Catalysis, Pisa, 1.–5. Mai 1995, 45-48