1. H.P. Röser, Thesis Bonn 1979
2. H.P. Röser, E. Sauter, G.V. Schultz, Agard Nato Symp. on MM- and Submm Wave Propagation and Circuits, Munich 1978
3. G.A. Koepf, N. McAvoy, Conf. on Infrared and Millimeter Waves, Miami 1979
4. P.M. Plainchamp, IEEE Journal of QE, Vol.QE-15, No 9
5. E. Sauter, H.P. Röser, W. Reinert, R. Wattenbach, G.V. Schultz, Conf. on Infrared and Millimeter Waves, Würzburg 1980