1. Bowles N (2017) CryptoKitties, explained … mostly.
https://www.nytimes.com/2017/12/28/style/cryptokitties-want-a-blockchain-snuggle.html
2. Bradbury D (2013) Colored coins paint sophisticated future for Bitcoin.
https://www.coindesk.com/colored-coins-paint-sophisticated-future-for-bitcoin
3. Buterin V (2012) Bitcoin adoption opportunity: teenagers.
https://bitcoinmagazine.com/articles/bitcoin-adoption-opportunity-teenager-1330407280/
4. Buterin V (2013) Mastercoin: a second-generation protocol on the Bitcoin blockchain.
https://bitcoinmagazine.com/articles/mastercoin-a-second-generation-protocol-on-the-bitcoin-blockchain-1383603310/
5. Buterin V (2014a) A next-generation smart contract and decentralized application platform.
https://github.com/ethereum/wiki/wiki/White-Paper