TY JOUR TI THE INTRODUCTION OF BLOCKCHAIN TECHNOLOGY IN THE ECONOMY AND FINANCIAL SECTOR KW blockchain KW cryptocurrencies KW smart contracts KW transaction costs KW decentralization KW digital economy KW distributed ledger KW international payments KW financial security KW fintech. JO Scientific Bulletin: finance, banking, investment AU Norec, N.K. PY 2025 IS 0 PB V.I. Vernadsky Crimean Federal University