# <li value="3">The file does not contain duplicates. Participating libraries must ensure that an authority record does not already exist before creating a new one. Consequently, participating libraries must update an existing authority record rather than create a new one when they wish to include additional information about the entity represented by the record (for example, a birth date).</li> | # <li value="3">The file does not contain duplicates. Participating libraries must ensure that an authority record does not already exist before creating a new one. Consequently, participating libraries must update an existing authority record rather than create a new one when they wish to include additional information about the entity represented by the record (for example, a birth date).</li> |