N.D. Cent. Code § 49-04-03

When the commission shall have prescribed the forms for accounts, records, or memoranda to be kept by any public utility for any of its business, it thereafter shall be unlawful for such public utility to keep any accounts, records, or memoranda of such business other than those prescribed by the commission and those prescribed by or under authority of any other state or of the United States, with the exception of such accounts, records, or memoranda as shall be explanatory of and supplemental to the accounts, records, or memoranda prescribed by the commission.