• Bernhardt, P. A., et al. (1998), Two-dimensional mapping of the plasma density in the upper atmosphere with computerised ionospheric tomography (CIT), Phys. Plasmas, 5(5), 20102021.
  • Daniell, R. E., L. D. Brown, D. N. Anderson, M. W. Fox, P. H. Doherty, D. T. Decker, J. J. Sojka, and R. W. Schunck (1995), PIM: A global ionospheric parameterization based on first principle models, Radio Sci., 30, 14991510.
  • Hajj, G. A., and L. J. Romans (1998), Ionospheric electron density profiles obtained with the Global Positioning System: Results from the GPS/MET experiment, Radio Sci., 33(1), 175190.
  • Healy, S. B., and J. R. Eyre (2000), Retrieving temperature, water vapour and surface pressure information from refractive index profiles derived by radio occultation: A simulation study, Q. J. R. Meteorol. Soc., 126, 16611683.
  • Hoeg, P., A. Hauchecorne, G. Kirchengast, S. Syndergaard, B. Belloul, R. Leitinger, and W. Rothleitner (1999), Derivation of atmospheric properties using the radio occultation technique, Tech. Rep. 95-4, Dan. Meteorol. Inst., Copenhagen.
  • Kuo, Y.-H., S. Sokolovskiy, R. A. Anthes, and F. Vandenberghe (2000), Assimilation of GPS radio occultation data for numerical weather prediction, Terr. Atmos. Oceanic Sci., 11(1), 157186.
  • Pi, X., G. A. Hajj, B. D. Wilson, G. Rosen, and C. Wang (2001), Ionospheric data assimilation using GPS, paper presented at International Beacon Satellite Symposium, Int. Union of Radio Sci., Brussels.
  • Pryse, S. E., L. Kersley, C. N. Mitchell, P. S. J. Spencer, and M. J. Williams (1998), A comparison of reconstruction techniques used in ionospheric tomography, Radio Sci., 33(6), 17671779.
  • Rodgers, C. D. (2000), Inverse Methods for Atmospheric Sounding: Theory and Practice, Ser. Atmos. Oceanic Planet. Phys., vol. 2, World Sci., River Edge, N. J.
  • Rogers, N. C., C. N. Mitchell, J. A. T. Heaton, P. S. Cannon, and L. Kersley (2001), The application of radio tomographic imaging to HF oblique incidence ray tracing, Radio Sci., 36(6), 15911598.
  • Schriener, W. S., S. V. Sokolovskii, C. Rocken, and D. C. Hunt (1999), Analysis and validation of GPS/MET radio occultation data in the ionosphere, Radio Sci., 34(4), 949966.
  • Wang, C., G. A. Hajj, X. Pi, and L. J. Romans (1999), The Development of an ionospheric data assimilation model, in 1999 Ionospheric Effects Symposium, edited by J. M. Goodman, pp. 385393, Off. of Nav. Res., Arlington, Va. (Available as PB2000-108001 from