Wickert, J., Beyerle, G., Schmidt, T., Marquardt, C., König, R., Grunwaldt, L., Reigber, C. (2003): GPS Radio Occultation with CHAMP. - In: Reigber, C., Lühr, H., Schwintzer, P. (Eds.), First CHAMP Mission Results for Gravity, Magnetic and Atmospheric Studies, Springer-Verlag, 371-383.