29 CFR 18.612: Writing used to refresh memory.

If a witness uses a writing to refresh memory for the purpose of testifying, either while testifying, or before testifying if the judge in the judge's discretion determines it is necessary in the interest of justice, an adverse party is entitled to have the writing produced at the hearing, to inspect it, to cross-examine the witness thereon, and to introduce in evidence those portions which relate to the testimony of the witness. If it is claimed that the writing contains matters not related to the subject matter of the testimony the judge shall examine the writing in camera, excise any portion not so related, and order delivery of the remainder to the party entitled thereto. Any portion withheld over objections shall be preserved and made available in the event of review. If a writing is not produced or delivered pursuant to order under this rule, the judge shall make any order justice requires.