进口换单，退货委托书的英语怎么说

没听说过退货委托书，只是接触过如下：
报关委托书 a power of attorney for declare customs
报检委托书 a power of attoney for declare CCIQ
发运委托书 shipment letter of instruction

Power of Attorney for Goods Refundment 退货委托书

你说的“进口换单”如果是“提货单”就叫做 Bill of Lading

希望对你有帮助

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