S. Ashrafinia, U. Pareek, M. Naeem, D. Lee, “Biogeography-based optimization for joint relay assignment and power allocation in cognitive radio systems”, Proceeding IEEE Symposium on
Swarm Intelligence (SIS), pp.1-8, 2011.
 J. Zou, H. Xiong, D. Wang, C.W. Chen, “Optimal power allocation for hybrid overlay/underlay spectrum sharing in multiband cognitive radio networks”, IEEE Trans. on Veh. Technol., Vol. 62, No. 4, pp. 1827-1837, May 2013.
 L. Musavian, S. Aissa, “Capacity and power allocation for spectrum sharing communications in fading channels”, IEEE Trans. on Wireless Commun., Vol. 8, No. 1, pp. 148–156, Jan. 2009.
 X. Gong, A. Ispas, G. Dartmann, G. Ascheid, “ Power allocation and performance analysis in spectrum sharing systems with statistical CSI”, IEEE Trans. on Wireless Commun., Vol 12, No. 4, pp. 1819-1831, Apr. 2013.
 C. Chang, J. Chang, “Optima design parameters in a multi hop packet radio network using random access techniques", Computer networks and ISDN systems, Vol. 5, No. 11 pp. 493-497, Nov. 1986.
 J. Lee, H. Wang, J.G. Andrews, D. Hong, “Outage probability of cognitive relay networks with interference constraints”, IEEE Trans. on Wireless Commun., Vol. 10, No. 2, Feb. 2011.
 M. Naeem, A. Anpalagan, M. Jaseemuddin, D. C. Lee, “Resource allocation techniques in cooperative cognitive radio networks, ” IEEE Commun. Surveys and Tutorials,
Vol. 16, No. 5, pp.729-744, May 2014.
 D. X. He, F.Y. Li, “Throughput and energy efficiency comparison of one hop, two hop, virtual relay and cooperative retransmission schems”, Proceeding European Wireless, pp.580-587, 2010.
 K.J.R. Liu, A.K. Sadek, W. Su, A. Kwasinski, “Cooperative communications and networking”, Cambridge university, Press 2008.
 R. Aghajani, R. Saadat, M.R. Aref, “Comparison of managed decode-and-forward scheme and common decode-and-forward scheme in cooperative communication systems”, Journal of Intelligent Procedures in Electrical Technology, Vol 6, No. 22, pp. 3-12, Summer 2015.
 I. Maric, R.D. Yates, “Bandwidth and power allocation for cooperative strategies in gassian relay network", IEEE Trans. On Inf. Theory, Vol. 56, No.4, pp. 1880-1889, Apr. 2010.
 O. Simeone, U. Spagnolini, Y. Bar-Ness, “Stable throughput of cognitive radios with and without relaying capability", IEEE Trans. On Commun., Vol. 55, No. 12, pp. 2351-2360, Dec. 2007.
 L. Musavian, S. Aissa, “Capacity and power allocation for spectrum sharing communications in fading channels,” IEEE Trans. on Wireless Commun.,Vol. 8, No. 1, pp. 148–156, Jan. 2009.
 Y.J.A. Zhang, A.M.C. So, “Optimal spectrum sharing in MIMO cognitive radio networks via semi definite programming,” IEEE J. on Sel. Areas Commun., Vol. 29, No.2, pp. 362–373, Feb. 2011.
 C. D. T. Thai, P. Popovski, “Rate regions for coordination of decodeand- forward relays and direct users,” Proceeding IEEE Int. Conf. Commun., pp.4468-4472, 2012.
 S.Y. Lien, K.C. Chen, Y.C. Liang, Y. Lin. “Cognitive radio resource managmant for future cellular networks” IEEE Trans. On Wireless Commun., Vol. 21, No.1, pp 70-79, Feb. 2014
 S. Weifeng, K. A. Sadek, K. J. Ray Liu, “Cooperative communication protocols in wireless networks: Performance analysis and optimum power allocation, ”, Wireless Personal Communications
Springer, Vol. 44, No. 2
, pp. 181-217, Jan. 2008
 F. Gomez-Cuba, R.A. Cacheda, F.G. Castano, “A survey on cooperative diversity for wireless networks”, IEEE Commun. Surveys & Tutorials, Vol.14, No.3, pp.822-835, Fall 2012.
 S. Zahedi, “On Reliable Communication Over Relay Networks”, Ph.D. thesis, Stanford Univ., 2005.
 R. Aghajani, R. Saadat, M.R. Aref, “Power allocation and performance analysis for incremental-selective decode-and-forward cooperative communications over Nakagami-m fading channels,” IEICE Trans. on Commu. ,Vol. E96-B, No. 6, pp.1531-1539, Jul. 2013.
 J. Mietzner, L. Lampe, R. Schober, “Distributed transmit power allocation for multihop cognitive radio systems”, IEEE Trans. On Wireless Commun., Vol. 8, No. 10, pp. 5187–5201. Oct. 2009.
 B. Bandemer, Q. Li, X.E. Lin, A. Paulrag, “Overhearing-based interference cancellation for relay networks”, Proceeding IEEE Veh. on Technol. Conf., pp. 1–5, Fall 2009.
 C. Thai, P. Popovski, “Coordinated direct and relay transmission with interference cancelation in wireless systems,” IEEE Commun. Lett., Vol. 15, No. 4, pp. 416–418, Apr. 2011,
 C.D.T. Thai, P. Popovski, “Rate regions for coordination of decodeand- forward relays and direct users,” Proceeding IEEE Int. Conf. on Commun., pp.4468-4472, 2012
 L. Lu, G.Y. Li, G. Wu, “Optimal power allocation for CR networks with direct and relay-aided transmissions,” IEEE Trans. on wireless commun., Vol. 12, No. 4, pp.1832-1842, Apr. 2013.