双方当事人可以在合同中约定合同争议所适用的法律，即法律适用条款，如“本合同所产生的一切争议均适用XX国法律”。签订法律适用条款后，仲裁机构或法院在处理合同纠纷时就应依据法律适用条款所选择的XX国法律来解释合同内容，对合同未尽事项也将适用该国法律以作补充。当事人在选择合同所适用的法律时，既可以选择当事人的国内法，也可以选择第三国法律；既可以是与合同有关的，也可以是与合同没有联系的。当事人还可以选择适用国际公约如《买卖合同公约》，或其他国际法律文件如《商事合同通则》等，但是，当事人所选择的法律应是实体法，不可以是冲突法律。

此外，在国际货物贸易中，一些国际组织或民间团体制定了一些标准合同格式或示范条款供有关当事人采用。例如，国际商会为制成品制定的《国际商会国际销售示范合同》（The ICC Model International Sale Contract，简称《示范合同》），联合国欧洲经济委员会对进出口成套设备、安装成套设备工程、钢铁产品以及谷物等交易都制定了标准合同格式，其中尤以《成套设备和机器出口供应一般条件》为国际贸易界所熟知。近年来，我国与澳大利亚、新西兰政府部门制定了《羊毛交易标准合同》，我国国际经贸仲裁委员会和我国国际商会仲裁研究所也制定了《成套设备进口合同（CIF条件）》供我国有关公司参考。这些标准合同格式都属于示范条款，当事人可以采用也可以不采用，还可以对条款进行修改、删除或补充。

课外阅读资料

一、CISG关于承诺的规定

Article 18：（1）A statement made by or other conduct of the offeree indicating assent to an offer is an acceptance. Silence or inactivity does not in itself amount to acceptance.

（2）An acceptance of an offer becomes effective at the moment the indication of assent reaches the offeror. An acceptance is not effective if the indication of assent does not reach the offeror within the time he has fixed or，if no time is fixed，within a reasonable time，due account being taken of the circumstances of the transaction，including the rapidity of the means of communication employed by the offeror. An oral offer must be accepted immediately unless the circumstances indicate otherwise.

（3）However，if，by virtue of the offer or as a result of practices which the parties have established between themselves or of usage，the offeree may indicate assent by performing an act，such as one relating to the dispatch of the goods or payment of the price，without notice to the offeror，the acceptance is effective at the moment the act is performed，provided that the act is performed within the period of time laid down in the preceding paragraph.

Article 19：（1）A reply to an offer which purports to be an acceptance but contains additions，limitations or other modifications is a rejection of the offer and constitutes a counter-offer.

（2）However，a reply to an offer which purports to be an acceptance but contains additional or different terms which do not materially alter the terms of the offer constitutes an acceptance，unless the offeror，without undue delay，objects orally to the discrepancy or dispatches a notice to that effect. If he does not so object，the terms of the contract are the terms of the offer with the modifications contained in the acceptance.

（3）Additional or different terms relating，among other things，to the price，payment，quality and quantity of the goods，place and time of delivery，extent of one party's liability to the other or the settlement of disputes are considered to alter the terms of the offer materially.

Article 20：（1）A period of time for acceptance fixed by the offeror in a telegram or a letter begins to run from the moment the telegram is handed in for dispatch or from the date shown on the letter or，if no such date is shown，from the date shown on the envelope. 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.

（2）Official holidays or non-business days occurring during the period for acceptance are included in calculating the period. However，if a notice of acceptance cannot be delivered at the address of the offeror on the last day of the period because that day falls on an official holiday or a non-business day at the place of business of the offeror，the period is extended until the first business day which follows.

Article 21：（1）A late acceptance is nevertheless effective as an acceptance if without delay the offeror orally so informs the offeree or dispatches a notice to that effect.

（2）If a letter or other writing containing a late acceptance shows that it has been sent in such circumstances that if its transmission had been normal it would have reached the offeror in due time，the late acceptance is effective as an acceptance unless，without delay，the offeror orally informs the offeree that he considers his offer as having lapsed or dispatches a notice to that effect.

Article 22：An acceptance may be withdrawn if the withdrawal reaches the offeror before or at the same time as the acceptance would have become effective.

Article 23：A contract is concluded at the moment when an acceptance of an offer becomes effective in accordance with the provisions of this Convention.(www.daowen.com)

Article 24：For the purposes of this Part of the Convention，an offer，declaration of acceptance or any other indication of intention "reaches" the addressee when it is made orally to him or delivered by any other means to him personally，to his place of business or mailing address or，if he does not have a place of business or mailing address，to his habitual residence.

二、CISG关于关于合同形式及保留的规定

Article 11：A contract of sale need not be concluded in or evidenced by writing and is not subject to any other requirement as to form. It may be proved by any means，including witnesses.

Article 12：Any provision of article 11，article 29 or Part II of this Convention that allows a contract of sale or its modification or termination by agreement or any offer，acceptance or other indication of intention to be made in any form other than in writing does not apply where any party has his place of business in a Contracting State which has made a declaration under article 96 of this Convention. The parties may not derogate from or vary the effect or this article.

Article 13：For the purposes of this Convention "writing" includes telegram and telex.

Article 96：A Contracting State whose legislation requires contracts of sale to be concluded in or evidenced by writing may at any time make a declaration in accordance with article 12 that any provision of article 11，article 29，or Part II of this Convention，that allows a contract of sale or its modification or termination by agreement or any offer，acceptance，or other indication of intention to be made in any form other than in writing，does not apply where any party has his place of business in that State.

【注释】

[1]张玉卿等编著：《联合国国际货物销售合同公约释义》，辽宁人民出版社，1988年版，第16页。

[2]张玉卿等编著：《联合国国际货物销售合同公约释义》，辽宁人民出版社，1988年版，第18页。

[3]翟云岭、郭杰著：《新合同法论》，大连海事大学出版社，2000年版，第55页。

[4]赵承壁著：《国际货物买卖合同》，对外贸易大学出版社，2001年版，第47页。

[5]翟云岭、郭杰著：《新合同法论》，大连海事大学出版社，2000年版，第181页。

[6]左海聪著：《国际贸易法》，法律出版社，2004年版，第66页。

[7]赵承壁著：《国际货物买卖合同》，对外贸易大学出版社，2001年版，第178页。

[8]王传丽主编：《国际贸易法》，中国政法大学出版社，2003年版，第104页。