1. Bitcoin Whitepaper – https://bitcoin.org/bitcoin.pdf.
2. List of published standards on Blockchain and distributed ledger technology systems https://www.iso.org/committee/6266604/x/catalogue/p/1/u/0/w/0/d/.
3. Shetty S.S., Kamhoua Ch.A., Njilla L.L., “Blockchain for distributed systems security”, PWN 2020.
4. Implementation of a durable medium based on blockchain technology in PKO BP https://fintech.pkobp.pl/blockchain-w-banku/.
5. Requirements for personal data protection contained in Regulation (EU) 2016/679 of the European Parliament and of the Council of 27 April 2016 on the protection of natural persons with regard to the processing of personal data and on the free movement of such data, and repealing Directive 95/46/EC (General Data Protection Regulation).