Vigna, Paul; Casey, Michael J. (2015). "Community". The Age of Cryptocurrency: How Bitcoin and the Blockchain Are Challenging ... Macmillan Publishers. p. 88. ISBN978-1-250-06563-6. Archived from the original on 5 August 2021. Retrieved 18 November 2020.
Vigna, Paul; Casey, Michael J. (2015). "Community". The Age of Cryptocurrency: How Bitcoin and the Blockchain Are Challenging ... Macmillan Publishers. p. 88. ISBN978-1-250-06563-6. Archived from the original on 5 August 2021. Retrieved 18 November 2020.