The two countries agree to the Exchange by signing a contract to purchase and payment details are the item delivery period. The monetary system is used to calculate the value of the debt, which will be the main currency.
The two countries agreed to exchange products bought and paid for by the contract. The Details Delivery Period Currency system that is used to calculate the debt, which is denominated in the main.
The two countries agreed to exchange products by contract and pay pay, the details of goods, delivery period Currency system to be used in the calculation of the value of settlements, which will be the main currency