1. Popper, B. (2015). Drones could make Amazon’s dream of free delivery profitable, The Verge. [Online]. Available: http://www.theverge.com/2015/6/3/8719659/amazon-prime-air-drone-delivery-profit-free-shipping-small-items . Accessed 22 Jun 2016.
2. Hutchinson, S. (2016). How not to lose your job to a Robot, Inverse. [Online]. Available: https://www.inverse.com/article/3232-why-drones-may-not-replace-your-delivery-guy . Accessed 23 Jun 2016.
3. D’Onfro. (2016). Amazon prime members may spend more than double what Non-Members Do, Business Insider. [Online]. Available: http://www.businessinsider.com/amazon-prime-members-may-spend-more-than-double-what-non-members-do-2015-1 . Accessed 14 May 2016.
4. Daim, T., & Oliver, T. (2008). Implementing technology roadmap process in the energy services sector: A case study of a government agency. Technological Forecasting and Social Change, 75(5), 687–720.
5. The First Urban Drone Delivery Just Happened In Nevada. (2016). Popular Science. [Online]. Available: http://www.popsci.com/first-urban-drone-delivery-successful . Accessed 13 Jun 2016.