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HMRC internal manual

VAT Small and Medium Enterprises Assurance Manual

References: Introduction

It is good practice to raise routine references on each visit to verify transactions withother traders and to provide a useful credibility tool for colleagues. Where possible,routine references should be raised to the Shadow Economy Team (SET) via the relevant riskTeam on supplies made by unregistered traders. However, if it is clear that a large amountof revenue may be at risk if the transactions are not verified promptly, you shouldconsider issuing urgent references.