1. The measurement of ionospheric absorption;Beynon,1957
2. Some observations of ionospheric movements;Bibl,1955
3. De l'origine des échos E sporadique: quelques données experimentales recueillies en France;Lepechinsky,1958
4. The reflexion and absorption of radio waves in the ionosphere;Piggott,1953
5. Discrepancies in the ionospheric absorption deduced from the first order and multiple order reflections;Piggott;URSI-AGI Committee,1959