1. [1] The GNU OpenPGP privacy handbook, 1999. Available at www.gnupg.org/gph/en/manual/book1.html.
2. [2] Black tulip: Report of the investigation into the diginotar certificate authority breach, 2012. Available at http://arkanoid.hu/stuff/Black retrieved on 1.05.2019.
3. [4] Carlisle Adams and Steve Lloyd. Understanding PKI: concepts, standards, and deployment considerations. Addison-Wesley Professional, 2003.
4. [7] Elli Androulaki, Christian Cachin, Angelo De Caro, Alessandro Sorniotti, and Marko Vukolic. Permissioned blockchains and hyperledger fabric. ERCIM News, 2017(110), 2017.
5. [10] Laurent Chuat, Pawel Szalachowsky, Adrian Perrig, Ben Laurie, and Eran Messeri. Efficient gossip protocols for verifying the consistency of certificate logs. In 2015 IEEE Conference on Communications and Network Security (CNS), 2015.