Account maintenance for specified goods creates a presumption of illegal export when stock falls short on verification. Persons who own, possess or control specified goods within a specified area must maintain a true and complete account of those goods, record each acquisition and parting with the goods, and keep the account with the goods at the place of storage. Where such goods are used in the manufacture of other goods, a separate account of the goods so used must be maintained at the intimated place. If verification shows a deficiency in stock against the accounts, it is presumed, unless the contrary is proved, that the missing goods were illegally exported and that the person concerned was involved.