What was established and NOT established under Roman Law?

Roman law is the legal system of ancient Rome, including the legal developments spanning over a thousand years of jurisprudence, from the Twelve Tables (c. 449 BC), to the Corpus Juris Civilis (AD 529) ordered by Eastern Roman Emperor Justinian I. Roman law forms the basic framework for civil law, the most widely used legal system today, and the terms are sometimes used synonymously. The historical importance of Roman law is reflected by the continued use of Latin legal terminology in many legal systems influenced by it, including common law.

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b.provides a written record of the transaction