Agents of the commission, upon specific written authorization signed by the chairman or secretary of the commission, shall have the right to inspect the premises, books, records, documents and all other instruments of any carrier, railroad, truck, boat, grower, shipper, dealer or retailer for the purpose of enforcing this chapter and collecting the assessments levied under authority of this chapter. In the event of refusal of any person to allow such inspection, the commission may apply to any court for the issuance of a subpoena to compel such inspection.