(1) Pursuant to 15-70-323, MCA, every special fuel user and every person importing, manufacturing, refining, dealing in, transporting, or storing special fuel in this state must maintain and keep records, receipts, invoices and other pertinent papers as the department requires and must produce them for the inspection of the department at any time during the business hours of the day.   Such records, receipts, invoices, and other pertinent papers must be kept with the corresponding special fuel user's tax return for a period of 3 years from the date the tax return relates.   For taxpayers falling under the International Fuel Tax Agreement, records have to be kept for 4 years.