1. Ionospheric investigation using the sweep-frequency pulse technique at oblique incidence;Agy;J. Res. NBS,1959
2. Study of radio wave propagation in sweep-frequency pulse transmission tests in Japan;Aono;J. Radio Res. Labs.,1962
3. Ionospheric Radio Propagation;CRPL (Central Radio Propagation Lab.);NBS Circular,1948
4. Ionospheric radio propagation;Davies;NBS Monograph,1965
5. Echolotungen der Ionosphäre mit veränderlicher Frequenz bei schrägem Einfall;Dieminger;NTZ-Nachrtech. Z.,1955