Archived from the original on 21 March 2015. ↑ Ittay Eyal with Emin Gün Sirer:"Majority is not Enough: Bitcoin Mining is Vulnerable Archived 2016-12-03 at the Wayback Machine." in the 18th International Conference on Financial Cryptography and Data Security(FC).2014 ↑ Eyal, Ittay.