国际回信券张宝芝国际回信券是一种可以兑换邮票的凭证。国际回信券由“万国邮政联盟”国际局统一印制，各国邮政部门可以根据情况决定出售与否，但各国邮政均应办理回信券的兑换业务。国际回信券内含有“ＵＰＵ”（邮联法文缩写）水纹字母，正面印有“万国邮政联盟”和“... International Reply Coupon Cheung Po Chi International Coupons is a voucher that can be exchanged for stamps. International Reply Coupons are printed uniformly by the “Universal Postal Union” International Bureau. Post offices in all countries may decide whether to sell or not, but postal exchanges should be conducted in all postal services. International Reply Coupons contain “UPU” (Postal Union French abbreviation) watermark letters printed on the front, “Universal Postal Union” and "...