53.176—Supporting evidence required in case of price readjustments.
No credit or refund of an overpayment arising by reason of a price readjustment described in § 53.174 or § 53.175 shall be allowed unless the manufacturer who paid the tax submits a statement, supported by sufficient available evidence:
(c)
Showing the price at which the article was sold, the amount of tax paid in respect of the article, and the date on which the tax was paid,