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2. European Central Bank, October 2012. Virtual Currency Schemes, available at: http://www.ecb.europa.eu/pub/pdf/other/virtualcurrencyschemes201210en.pdf.
3. FBI, 24 April 2012. Bitcoin Virtual Currency: Unique Features Present Distinct Challenges for Deterring Illicit Activity, available at: http://www.wired.com/images_blogs/threatlevel/2012/05/Bitcoin-FBI.pdf.
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