Exhibition of certificate of payment at place of business.
Section 219
SEC. 219. Exhibition of certificate of payment at place of business.—The certificate or receipts showing payment of tax issued to a person engaged in a business subject to a privilege tax shall be kept conspicuously exhibited in plain view in or at the place where the business is conducted ; and, in case of a peddler or other persons not having a fixed place of business, shall be kept in the possession of the holder thereof, subject to production upon the demand of any internal revenue officer.