A signed invoice presumes receipt of the shipment.
经过签收的发货单表示运去货物已收到。
2
Fee payments should be made within 30 days of the receipt of the invoice or by the due date of the invoice whichever is earlier.
家长在收到账单30天之内或账单到期日之前（以较早日期为准）应支付相应费用。
3
The organizer will give the receipt to exhibitors first after receiving charges, then the exhibitors will exchange receipt for invoice during the exhibition period.