Article 19 Irrevocable Offer An offer may not be revoked: (i) if it expressly indicates, whether by stating a fixed time for acceptance or otherwise, that it is irrevocable;
第十九条有下列情形之一的，要约不得撤销：（一）要约人确定了承诺期限或者以其他形式明示要约不可撤销；
A period of time for acceptance fixed by the offeror by telephone, telex or other means of instantaneous communication, Begins to run from the moment that the offer reaches the offeree.
发盘人以电话、电传或其它快速通讯方法规定的接受期间，以发盘送达受盘人时起算。
应用推荐