1. Omar Siddiqui and George V. Eleftheriades,“Resonant Modes in Continuous metallic grids over ground and related spatial-filtering applications”, Journal of Applied Physics, vol 99, pp 083102- 083110, April, 2006.

2. G.V.Eleftheriades and O.F. Siddiqui, "Negative refraction and focusing in hyperbolic transmission-line grids," IEEE Transactions on Microwave Theory and Techniques, vol. 53, no. 1,pp. 396-403, January, 2005.

3. Omar Siddiqui and George V. Eleftheriades , “Resonance-cone focusing in a compensating bilayer of continuous hyperbolic microstrip grids”, Applied Physics Letters, vol 85, pp 1292,August 2004.

4. O.F. Siddiqui, S.J. Erickson, G.V. Eleftheriades and M. Mojahedi, "Time-domain Measurement of negative group delay in negative-refractive-index transmission-line metamaterials,"IEEE Trans. on Microwave Theory and Techniques, vol.52, no. 5, pp. 1449-1454 , May, 2004.

5. O. Siddiqui, M. Mojahedi, and G.V. Eleftheriades, “Periodically loaded transmission line with negative refractive index and negative group velocity,” IEEE Trans. On Antennas and Propagation, vol. 51,no. 10, 2619-2625, Oct. 2003.

6. G.V. Eleftheriades, O. Siddiqui and A.K. Iyer, “Transmission line models for negative refractive index media and associated implementations without excess resonators.” IEEE Microwave and Wireless Components Leters, vol. 13, no.2, pp.51-53,Feb. 2003.