1. Chew, W. C. and Y. M. Wang, "Reconstruction of two-dimensional permittivity distribution using the distorted Born iterative method," IEEE Trans. Med. Imag., Vol. 9, No. 2, 218-225, 1990.
doi:10.1109/42.56334

2. Zaeytijd, D., J. Franchois, A. C. Eyraud, and J. M. Geffrin, "Full-wave three-dimensional microwave imaging with a regularized Gauss-Newton method --- Theory and experiment," IEEE Trans. on Antennas Propagat., Vol. 55, No. 11, 3279-3292, 2007.
doi:10.1109/TAP.2007.908824

3. Otto, G. P. and W. C. Chew, "Microwave inverse scattering-local shape function imaging for improved resolution of strong scatterers," IEEE Trans. Microwave Theory Tech., Vol. 42, No. 1, 137-141, 1994.
doi:10.1109/22.265541

4. Franchois, A. and C. Pichot, "Microwave imaging-complex permittivity reconstruction with a Levenberg-Marquardt method," IEEE Trans. Antennas Propagat., Vol. 45, No. 2, 203-214, 1997.
doi:10.1109/8.560338

5. Van Dongen, K. W. A. and W. M. D. Wright, "A full vectorial contrast source inversion scheme for three-dimensional acoustic imaging of both compressibility and density profiles," The Journal of the Acoustical Society of America, Vol. 121, 1538-1549, 2007.
doi:10.1121/1.2431333

6. Bucci, O. M., L. Crocco, T. Isernia, and V. Pascazio, "Inverse scattering problems with multifrequency data: Reconstruction capabilities and solution strategies," IEEE Trans. Geosci. Remote Sensing, Vol. 38, No. 4, 1749-1756, 2000.
doi:10.1109/36.851974

7. Cui, T. J., Y. Qin, Y. Ye, J. Wu, G. L. Wang, and W. C. Chew, "Efficient low-frequency inversion of 3-D buried objects with large contrasts," IEEE Trans. Geosci. Remote Sensing, Vol. 44, No. 1, 3-9, 2006.
doi:10.1109/TGRS.2005.860207

8. Pastorino, M., A. Massa, and S. Caorsi, "A microwave inverse scattering technique for image reconstruction based on a genetic algorithm," IEEE Trans. Instrumentation and Measurement, Vol. 49, No. 3, 573-578, 2000.
doi:10.1109/19.850397

9. Isernia, T., V. Pascazio, and R. Pierri, "On the local minima in a tomographic imaging technique," IEEE Trans. Geosci. Remote Sensing, Vol. 39, No. 7, 1596-1607, 2001.
doi:10.1109/36.934091

10. Caorsi, S., M. Donelli, D. Franceschini, and A. Massa, "An iterative multiresolution approach for microwave imaging applications," Microwave Opt. Technol. Lett., Vol. 32, No. 5, 352-356, 2002.
doi:10.1002/mop.10175

11. Joachimowicz, N., C. Pichot, and J. Hugonin, "Inverse scattering: an iterative numerical method for electromagnetic imaging," IEEE Trans. Antennas Propagat., Vol. 39, No. 12, 1742-1752, 1991.
doi:10.1109/8.121595

12. Lin, J.-H. and W. C. Chew, "Solution of the three-dimensional electromagnetic inverse problem by the local shape function and the conjugate gradient fast Fourier transform methods," J. Opt. Soc. Am. A, Vol. 14, No. 11, 3037-3045, 1997.
doi:10.1364/JOSAA.14.003037

13. Abubakar, A., P. M. van den Berg, and B. Kooij, "A conjugate gradient contrast source technique for 3D profile inversion," IEICE Trans. Electron. E83-C, 1864-1874, 2000.

14. Song, L. P. and Q. H. Liu, "Fast three-dimensional electromagnetic nonlinear inversion in layered media with a novel scattering approximation," Inverse Problems, Vol. 20, 171-194, 2004.
doi:10.1088/0266-5611/20/6/S11

15. Moghaddam, M. and W. C. Chew, "Study of some practical issues in inversion with the Born iterative method using time-domain data," IEEE Trans. Antennas Propagt., Vol. 41, No. 2, 177-184, 1993.
doi:10.1109/8.214608

16. Fhager, A., P. Hashemzadeh, and M. Persson, "Reconstruction quality and spectral content of an electromagnetic time-domain inversion algorithm," IEEE Trans. on Biomedical Eng., Vol. 53, 1594-1604, 2006.
doi:10.1109/TBME.2006.878079

17. He, S., P. Fuks, and G. W. Larson, "Optimization approach to time-domain electromagnetic inverse problem for a stratified dispersive and dissipative slab," IEEE Trans. Antennas Propagat., Vol. 44, No. 9, 1277-1282, 1996.
doi:10.1109/8.535386

18. Yu, W. H. and R. Mittra, "A nonlinear optimization technique for reconstructing dielectric scatterers with possible high contrasts," Microwave Opt. Technol. Lett., Vol. 14, No. 2, 268-271, 1997.
doi:10.1002/(SICI)1098-2760(19970405)14:5<268::AID-MOP4>3.0.CO;2-B

19. Gustafsson, M. and S. He, "An optimization approach to two-dimensional time domain electromagnetic inverse problems," Radio Sci., Vol. 35, 525-536, 2000.
doi:10.1029/1999RS900091

20. Takenaka, T., H. Zhou, and T. Tanaka, "Inverse scattering for a three-dimensional object in the time domain," J. Opt. Soc. Am. A, Vol. 20, No. 10, 1867-1874, 2003.
doi:10.1364/JOSAA.20.001867

21. Zhou, H., M. Sato, T. Takenaka, and G. Li, "Reconstruction from antenna transformed radar data using a time-domain reconstruction method," IEEE Trans. Geosci. Remote Sensing, Vol. 45, No. 3, 689-696, 2007.
doi:10.1109/TGRS.2006.888140

22. Tanaka, T., N. Kuroki, and T. Takenaka, "Filtered forward-backward time-stepping method applied to reconstruction of dielectric cylinders," J. Electromagn. Waves Appl., Vol. 17, No. 2, 253-270, 2003.
doi:10.1163/156939303322235815

23. Zhou, H., D. L. Qiu, and T. Takenaka, "Reconstructing properties of subsurface from Ground-penetrating radar data," Progress In Electromagnetics Research Symposium 2007, 1009-1014, Beijing, China, March 26-30, 2007.

24. Daniels, D. J., Surface-penetrating Radar, UK Instit Elect Eng., 1996.

25. Broquetas, A., J. Romeu, J. M. Rius, A. R. Elias-Fuste, et al. "Cylindrical geometry: A further step in active microwave tomography," IEEE Trans. Microwave Theory Tech., Vol. 39, No. 5, 836-844, 1991.
doi:10.1109/22.79111

26. Bloemenkamp, R. F., A. Abubakar, and P. M. van den Berg, "Inversion of experimental multi-frequency data using the contrast source inversion method," Inverse Problems, Vol. 17, 1611-1622, 2001.
doi:10.1088/0266-5611/17/6/305