The retail selling price of products sold by the resellers referred to in the first paragraph of article 568 and products delivered to travellers by the purchaser-resellers designated in the twelfth paragraph of this article is freely determined, although this price may not be lower than the retail price expressed per 1,000 units or per 1,000 grams specified in the approval order. Purchaser-resellers are obliged to enter in their stock accounts and to declare on the duty settlement declaration all price changes occurring during the period covered by the said declaration.
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