<https://tincoinviet.net/dich-vu-tao-hop-dong-thong-minh-smart-contract-vakaxa/>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://tincoinviet.net/dich-vu-tao-hop-dong-thong-minh-smart-contract-vakaxa/>