1. S.V. Yumlu, Particulate traps: some progress, some problems, SAE Paper 880347.
2. P. Zelenka, K. Ostgathe and E. Lox, Reduction of diesel exhaust emissions by using oxidation catalysts, SAE-Paper 902111.
3. P.L. Herzog, L. Bürgler, Winklhofer, P. Zelenka and W. Cartellieri, NOx reduction strategies for DI diesel engines, SAE-Paper 920470.