1. Poynting, J. H., "The wave motion of a revolving shaft, and a suggestion as to the angular momentum in a beam of circularly polarised light," Proceedings of the Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character, Vol. 82, No. 5, 560-567, 1909.

2. Beth, R. A., "Mechanical detection and measurement of the angular momentum of light," Physical Review, Vol. 50, No. 2, 115-125, 1936.
doi:10.1103/PhysRev.50.115

3. Allen, L., M. W. Beijersbergen, R. J. Spreeuw, and J. P. Woerdman, "Orbital angular-momentum of light and the transformation of Laguerre-Gaussian laser modes," Physical Review A, Vol. 45, No. 11, 8185-8189, 1992.
doi:10.1103/PhysRevA.45.8185

4. Chen, R., H. Zhou, M. Moretti, X. Wang, and J. Li, "Orbital angular momentum waves: generation, detection and emerging applications,", arXiv preprint arXiv:1903.07818, Mar. 2019.

5. Thide, B., H. Then, J. Sjoholm, K. Palmer, J. Bergman, T. D. Carozzi, Y. N. Istomin, N. H. Ibragimov, and R. Khamitova, "Utilization of photon orbital angular momentum in the low-frequency radio domain," Physical Review Letters, Vol. 99, No. 8, 087701-1-087701-4, Aug. 2007.
doi:10.1103/PhysRevLett.99.087701

6. Durnin, J. J. J. M., J. J. Miceli, Jr, and J. H. Eberly, "Diffraction-free beams," Physical Review Letters, Vol. 58, No. 15, 1499-1501, Apr. 1987.
doi:10.1103/PhysRevLett.58.1499

7. Barbuto, M., F. Trotta, F. Bilotti, and A. Toscano, "Circular polarized patch antenna generating orbital angular momentum," Progress In Electromagnetics Research, Vol. 148, 23-30, 2014.
doi:10.2528/PIER14050204

8. Huang, M., X. Zong, and Z. P. Nie, "Horn antenna generating electromagnetic field with orbital angular momentum," Progress In Electromagnetics Research M, Vol. 60, 57-65, 2017.
doi:10.2528/PIERM17030801

9. Al-Bassam, A., M. A. Salem, and C. Caloz, "Vortex beam generation using circular leaky-wave antenna," IEEE Antennas and Propagation Society International Symposium (APSURSI), 1792-1793, 2014.
doi:10.1109/APS.2014.6905222

10. Ettorre, M. and A. Grbic, "Generation of propagating Bessel beams using leaky-wave modes," IEEE Transactions on Antennas and Propagation, Vol. 60, No. 8, 3605-3613, 2012.
doi:10.1109/TAP.2012.2201088

11. Lu, P., D. Voyer, A. Br´eard, J. Huillery, B. Allard, X. Lin-Shi, and X. S. Yang, "Design of TEpolarized bessel antenna in microwave range using leaky-wave modes," IEEE Transactions on Antennas and Propagation, Vol. 66, No. 1, 32-41, 2018.
doi:10.1109/TAP.2017.2768584

12. Dheyab, E. and N. Qasem, "Design and optimization of rectangular microstrip patch array antenna using frequency selective surfaces for 60 GHz," International Journal of Applied Engineering Research, Vol. 11, No. 7, 4679-4687, 2016.

13. Pelin, N., M. H. Salem, E. Niver, and M. A. Salem, "Microwave vortex beam launcher design," IET Journal on Microwaves, Antennas & Propagation, Vol. 12, No. 14, 2149-2153, 2018.
doi:10.1049/iet-map.2018.5007

14. Mao, F., T. Li, Y. Shao, J. Yang, and M. Huang, "Orbital angular momentum radiation from circular patches," Progress In Electromagnetics Research Letters, Vol. 61, 13-18, 2016.
doi:10.2528/PIERL16012604

15. Hui, X., S. Zheng, Y. Chen, Y. Hu, X. Jin, H. Chi, and X. Zhang, "Multiplexed millimeter wave communication with dual orbital angular momentum (OAM) mode antennas," Scientific Reports, Vol. 5, No. 1, 1-9, 2015.
doi:10.9734/JSRR/2015/14076

16. Berglind, E. and G. Bjork, "Humblet’s decomposition of the electromagnetic angular moment in metallic waveguides," IEEE Transactions on Microwave Theory and Techniques, Vol. 62, No. 4, 779-788, 2014.
doi:10.1109/TMTT.2014.2308891

17. Alamayreh, A., N. Qasem, and J. Rahhal, "General configuration MIMO system with arbitrary OAM," Electromagnetics, Vol. 40, No. 5, 343-353, 2020.
doi:10.1080/02726343.2020.1780378

18. Cheng, W., H. Zhang, L. Liang, H. Jing, and Z. Li, "Orbital-angular-momentum embedded massive MIMO: Achieving multiplicative spectrum-efficiency for mmWave communications," IEEE Access, Vol. 6, 2732-2745, 2017.

19. Zheng, S., Y. Chen, Z. Zhang, X. Jin, H. Chi, X. Zhang, and Z. N. Chen, "Realization of beam steering based on plane spiral orbital angular momentum wave," IEEE Transactions on Antennas and Propagation, Vol. 66, No. 3, 1352-1358, 2017.
doi:10.1109/TAP.2017.2786297

20. Cheng, W., W. Zhang, H. Jing, S. Gao, and H. Zhang, "Orbital angular momentum for wireless communications," IEEE Wireless Communications, Vol. 26, No. 1, 100-107, 2018.
doi:10.1109/MWC.2017.1700370

21. Astley, V., B. McCracken, R. Mendis, and D. M. Mittleman, "Analysis of rectangular resonant cavities in terahertz parallel-plate waveguides," Optics Letters, Vol. 36, No. 8, 1452-1454, 2011.
doi:10.1364/OL.36.001452

22. Balanis, C. A., Advanced Engineering Electromagnetic, John Wiley & Sons, New York, 1989.

23. Collin, R. E., Foundations for Microwave Engineering, McGraw-Hill, New York, 1966.

24. Fuscaldo, W., G. Valerio, A. Galli, R. Sauleau, A. Grbic, and M. Ettorre, "Higher-order leaky-mode bessel-beam launcher," IEEE Transactions on Antennas and Propagation, Vol. 64, No. 3, 904-913, 2015.
doi:10.1109/TAP.2015.2513076

25. King, R. W. P., "The loop antenna for transmission and reception," Antenna Theory, Part 1, 1st Edition, Inter-University Electronic Series, Vol. 7, Chap. 11, 458–482, R. E. Collin and F. J. Zucker, ed., McGraw-Hill, New York, 1969.

26. Sutinjo, A., M. Okoniewski, and R. H. Johnston, "Radiation from fast and slow traveling waves," IEEE Antennas and Propagation Magazine, Vol. 50, No. 4, 175-181, 2008.
doi:10.1109/MAP.2008.4653700

27. Jackson, D. R. and A. A. Oliner, "Leaky-wave antennas," Modern Antenna Handbook, Chap. 7, 325–367, C. Balanis, ed., Wiley, New York, NY, USA, 2008.

28. Knudsen, H. L., "The field radiated by a ring quasi-array of an infinite number of tangential or radial dipoles," Proceedings of the IRE, Vol. 41, No. 6, 781-789, 1953.
doi:10.1109/JRPROC.1953.274261