1. IoT Analytics. Why the internet of things is called internet of things: Definition, history, disambiguation.
https://iot-analytics.com/internet-of-things-definition/
2. Gartner Research. Gartner says 6.4 billion connected things will be in use in 2016, up 30 percent from 2015.
http://www.gartner.com/newsroom/id/3165317
3. Juniper Research. Internet of things connected devices to almost triple to over 38 billion units by 2020.
http://www.juniperresearch.com/press/press-releases/iot-connected-devices-to-triple-to-38-bn-by-2020
4. The Statistics Portal. Internet of things (iot): number of connected devices worldwide from 2012 to 2020 (in billions).
http://www.statista.com/statistics/471264/iot-number-of-connected-devices-worldwide/
5. Sharma SK, Wang X (2017) Live data analytics with collaborative edge and cloud processing in wireless iot networks. IEEE Access 5:4621–4635