1. Modeling the total electron content;Anderson;J. Geophys. Res.,1983
2. Model representation of mid-latitudinal electron density by means of Interkosmos-19 data;Benkova;Adv. Space Res.,1984
3. Bent , R. B. S. K. Llewellyn Description of the 1965-71 ionospheric model used in the Definitive Orbit Determination System (DODS Report DBA-Systems 1970
4. Fitting of multiregion ionospheric profiles of electron density by a single analytic function of height;Booker;J. Atmos. Terr. Phys.,1977
5. Lincoln , J. V. R. O. Conkright International Reference Ionosphere - IRI 79 1981