1. Cisco visual networking index: Global mobile data traffic forecast update, 2014–2019 (2015). http://www.cisco.com/c/en/us/solutions/collateral/service-provider/visual-networking-index-vni/white_paper_c11-520862.html .
2. Gabriel, C. (2013). WBA industry report 2013: Global trends in public Wi-Fi. http://www.wballiance.com/wba/wp-content/uploads/downloads/2013/11/WBA-Industry-Report-2013.pdf .
3. Yilmaz, H., Tugcu, T., Alagöz, F., & Bayhan, S. (2013). Radio environment map as enabler for practical cognitive radio networks. IEEE Communications Magazine, 51(12), 162–169. doi: 10.1109/MCOM.2013.6685772 .
4. Evolved universal terrestrial radio access (E-UTRA); further advancements for E-UTRA physical layer aspects, TR. 36.814 v9.0.0. Technical report, 3GPP (2010)
5. Nie, N., & Comaniciu, C. (2006). Adaptive channel allocation spectrum etiquette for cognitive radio networks. Mobile Networks and Applications, 11(6), 779–797. doi: 10.1007/s11036-006-0049 .