26 USC 5415 - Records and returns

(a) Records 
Every brewer shall keep records, in such form and containing such information as the Secretary shall prescribe by regulations as necessary for protection of the revenue. These records shall be preserved by the person required to keep such records for such period as the Secretary shall by regulations prescribe, and shall be available during business hours for examination and taking of abstracts therefrom by any internal revenue officer.
(b) Returns 
Every brewer shall make true and accurate returns of his operations and transactions in the form, at the times, and for such periods as the Secretary shall by regulation prescribe.