https://123dok.net/document/dy4o14kz-rapport-national-sur-les-travaux-francais-executes-de-1975-a-1978-dans-la-discipline-ionosphere-magnetosphere-chapitre-iii-de-la-section-iv-du-rapport-national-presente-a-l-a-g-de-l-uggi-canberra-1979.html