1. Mongia, R.K., Hong, J., Bhartia, P. and Bahl, I.J., "Rf and microwave coupled-line circuits, Artech house, (2007).
2. Yeung, L.K. and Wu, K.-L., "A dual-band coupled-line balun filter", IEEE Transactions on Microwave Theory and Techniques, Vol. 55, No. 11, (2007), 2406-2411.
3. Tabatabaeian, Z.S. and Neshati, M.H., "Design investigation of a wideband backward-wave directional coupler using neural network", in Electrical Engineering (ICEE), 2016 24th Iranian Conference on, IEEE., (2016) 1394-1398.
4. Tabatabaeian, Z.S. and Neshati, M.H., "Development of a low profile and wideband backward-wave directional coupler using neural network", Applied Computational Electromagnetics Society Journal, Vol. 31, No. 12, (2016), 1404-1409.
5. Pourzadi, A., Attari, A.R. and Majedi, M.S., "A directivity-enhanced directional coupler using epsilon negative transmission line", IEEE Transactions on Microwave Theory and Techniques, Vol. 60, No. 11, (2012), 3395-3402.
6. Keshavarz, R., Movahhedi, M., Hakimi, A. and Abdipour, A., "A novel broad bandwidth and compact backward coupler with high couplinglevel", Journal of Electromagnetic Waves and Applications, Vol. 25, No. 2-3, (2011), 283-293.
7. Caloz, C. and Itoh, T., "A novel mixed conventional microstrip and composite right/left-handed backward-wave directional coupler with broadband and tight coupling characteristics", IEEE Microwave and Wireless Components Letters, Vol. 14, No. 1, (2004), 31-33.
8. Tabatabaeian, Z.S. and Neshati, M.H., "Development of a forward-wave directional coupler loaded with a periodic shunt structure", in Telecommunications (IST), 2016 8th International Symposium on, IEEE., (2016), 586-590.
9. Tabatabaeian, Z.S. and Neshati, M.H., "Development of forward-wave directional couplers loaded by periodic shunt shorted stubs", International Journal of Engineering-Transactions C: Aspects, Vol. 30, No. 3, (2017), 344-352.
10. Yen, J.-C., Hsu, S.-K., Lin, T.-H. and Wu, T.-L., "A broadband forward-wave directional coupler using periodic y-shaped ground via structures with arbitrary coupling levels", IEEE Transactions on Microwave Theory and Techniques, Vol. 61, No. 1, (2013), 38-47.
11. Hsu, S.-K., Tsai, C.-H. and Wu, T.-L., "A novel miniaturized forward-wave directional coupler with periodical mushroom-shaped ground plane", IEEE Transactions on Microwave Theory and Techniques, Vol. 58, No. 8, (2010), 2277-2283.
12. Ha, J. and Lee, Y., "Miniaturized quasi-asymmetric forward-wave coupled-line coupler with arbitrary coupling level", in Microwave Symposium Digest (IMS), 2013 IEEE MTT-S International, IEEE., (2013), 1-3.
13. Ha, J. and Lee, Y., "Generalised capacitive-loading method for miniaturisation of forward-wave directional coupled-line couplers with arbitrary strip impedances and coupling levels", IET Microwaves, Antennas & Propagation, Vol. 10, No. 5, (2016), 494-501.
14. Tabatabaeian, Z.S. and Neshati, M.H., "Development of broadband forward‐wave directional couplers loaded by periodic patterned ground structure", International Journal of RF and Microwave Computer‐Aided Engineering, Vol. 27, No. 8, (2017), 1-9.
15. Tabatabaeian, Z.S. and Neshati, M.H., "Design investigation of an x-band siw h-plane band pass filter with improved stop band using neural network optimization", Applied Computational Electromagnetics Society Journal, Vol. 30, No. 10, (2015), 1083-1088.