Sources:  
1.          Dean, J. (12/08/2017). “Plundering of £52m highlights dangers in the digital gold rush”, The Times (London/Ireland). URL: https://www.thetimes.co.uk/article/bitcoin-plundering-of-52m-highlights-dangers-in-the-digital-gold-rush-m3q3f9rvd 
2.          Brockett, M. (12/09/2017). “Bitcoin ‘Looks Remarkably Like A Bubble,’ New Zealand’s Central Banker Warns”. URL: https://www.bloomberg.com/news/articles/2017-12-09/bitcoin-looks-like-bubble-new-zealand-s-central-banker-warns 
3.          Associated Press. (12/11/2017 ). “Bitcoin futures soar amid frenzy over virtual currency.” Chicago Tribune. URL: http://www.chicagotribune.com/business/ct-bitcoin-futures-rise-20171210-story.html 
4.          Bird, Steven, Edward Loper and Ewan Klein (2009), Natural Language Processing with Python. O’Reilly Media Inc. 
5.          Frankel, M (2017). Is a Bitcoin IRA right for you? TheMotleyFool, URL: https://www.fool.com/retirement/2017/10/01/is-a-bitcoin-ira-right-for-you.aspx 
6.          Popper, N.(2015) Bitcoin Exchange Receives First License in New York State. New York Times. URL:https://www.nytimes.com/2015/05/08/business/dealbook/bitcoin-exchange-receives-first-license-in-new-york-state.html 
7.          New York State Department of Financial Services. (2015). “Title 23. Chapter 1 Regulations of the Superintendent of Financial Services. Part 200 Virtual Currencies” URL : http://www.dfs.ny.gov/legal/regulations/adoptions/dfsp200t.pdf 
8.          Databases: LexisNexis and WorldNews Access to collect data.
9.          Shin, L. (2017). What Bitcoin’s History Says About its Future. Forbes. URL: https://www.forbes.com/sites/laurashin/2017/11/14/what-bitcoins-history-says-about-its-future/#28faaa1c67d8
10. https://github.com/coffee1league/PUI2017_as9788
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