ISSN 0099-9660. Retrieved 2022-01-16. ↑ Andrychowicz, Marcin; Dziembowski, Stefan; Malinowski, Daniel; Mazurek, Łukasz (2015), "On the Malleability of Bitcoin Transactions", Financial Cryptography and Data Security, Berlin, Heidelberg: Springer Berlin Heidelberg, pp. 1–18, doi:10.1007/978-3-662-48051-9_1, ISBN 978-3-662-48050-2, retrieved 2021-07-11 ↑ Chavez-Dreyfuss, Gertrude (30 April 2019). "Cryptocurrency thefts, fraud hit $1.2 billion in first quarter: report".