[1] M. M. Alizadeh Elizei, "Multi-dimensional modeling of the ionospheric parameters, using space geodetic techniques," 2013.
[2] M. Bender, G. Dick, M. Ge, Z. Deng, J. Wickert, H.-G. Kahle, et al., "Development of a GNSS water vapour tomography system using algebraic reconstruction techniques," Advances in Space Research, vol. 47, pp. 1704-1720, 2011.
[3] M. Bevis, S. Businger, T. A. Herring, C. Rocken, R. A. Anthes, and R. H. Ware, "GPS meteorology: Remote sensing of atmospheric water vapor using the global positioning system," Journal of Geophysical Research: Atmospheres, vol. 97, pp. 15787-15801, 1992.
[4] J. Saastamoinen, "Atmospheric correction for the troposphere and stratosphere in radio ranging satellites," The use of artificial satellites for geodesy, vol. 15, pp. 247-251, 1972.
[5] H. Hopfield, "Two‐quartic tropospheric refractivity profile for correcting satellite data," Journal of Geophysical research, vol. 74, pp. 4487-4499, 1969.
[6] J. S. Subirana, M. Hernandez-Pajares, and J. e. M. J. Zornoza, GNSS Data Processing: Fundamentals and Algorithms: European Space Agency, 2013.
[7] M. Bender and G. Dick, "GNSS water vapor tomography," in Springer Handbook of Atmospheric Measurements, ed: Springer, 2021, pp. 1025-1049.
[8] P. Tregoning, R. Boers, D. O'Brien, and M. Hendy, "Accuracy of absolute precipitable water vapor estimates from GPS observations," Journal of geophysical research: atmospheres, vol. 103, pp. 28701-28710, 1998.
[9] A. Flores, G. Ruffini, and A. Rius, "4D tropospheric tomography using GPS slant wet delays," in Annales geophysicae, 2000, pp. 223-234.
[10] K. Hirahara, "Local GPS tropospheric tomography," Earth, planets and space, vol. 52, pp. 935-939, 2000.
[11] T. Nilsson and L. Gradinarsky, "Water vapor tomography using GPS phase observations: simulation results," IEEE Transactions on Geoscience and remote sensing, vol. 44, pp. 2927-2941, 2006.
[12] N. Ding, S. Zhang, and Q. Zhang, "New parameterized model for GPS water vapor tomography," in Annales Geophysicae, 2017, pp. 311-323.
[13] P. Xia, C. Cai, and Z. Liu, "GNSS troposphere tomography based on two-step reconstructions using GPS observations and COSMIC profiles," in Annales Geophysicae, 2013, pp. 1805-1815.
[14] G. Haines, "Spherical cap harmonic analysis," Journal of Geophysical Research: Solid Earth, vol. 90, pp. 2583-2591, 1985.
[15] Z. Liu, Ionosphere tomographic modeling and applications using Global Positioning System (GPS) measurements: university of Calgary, 2004.
[16] O. J. S. AL-FANEK, "Ionospheric imaging for Canadian polar regions," 2013.
[17] S. Farzaneh and E. Forootan, "Reconstructing regional ionospheric electron density: a combined spherical Slepian function and empirical orthogonal function approach," Surveys in geophysics, vol. 39, pp. 289-309, 2018.
[18] M. Schmidt, D. Dettmering, M. Mößmer, Y. Wang, and J. Zhang, "Comparison of spherical harmonic and B spline models for the vertical total electron content," Radio Science, vol. 46, pp. 1-8, 2011.
[19] D. Perler, A. Geiger, and F. Hurter, "4D GPS water vapor tomography: new parameterized approaches," Journal of Geodesy, vol. 85, pp. 539-550, 2011.
[20] P. C. Hansen, "The discrete Picard condition for discrete ill-posed problems," BIT Numerical Mathematics, vol. 30, pp. 658-672, 1990.
[21] H. Björnsson and S. Venegas, "A manual for EOF and SVD analyses of climatic data," CCGCR Report, vol. 97, pp. 112-134, 1997