The first of these groups consists of articles pertaining to international law and treaties. Article 90 states that it is the duty of government to promote the international rule of law. The Netherlands is home to several International Courts. Doctrine holds that this article also attributes the general right to conclude treaties. Article 91 states that the Kingdom shall not be bound by treaty without prior approval of the States General, except for those cases where law determines no such approval is necessary. Such approval may be tacit (Subarticle 2). Despite this, if not either a reservation of approval is made on conclusion of the treaty, or the treaty contains a ratification clause, treaties are according to international law binding upon conclusion. The article must thus be seen as imposing a duty upon government to arrange for such reservation or clause. Subarticle 3 determines that if a treaty conflicts with the Constitution, it has to be approved by a two-thirds majority of both Houses. Whether such conflict exists is decided by the States General; article 6 of the lower "Rijkswet goedkeuring en bekendmaking verdragen" determines that this decision has again to be made by special formal law. A special implementation by law of the 1992 Treaty of Maastricht determines that certain European Community decisions having force of treaty have to be approved by Parliament prior to even the conclusion itself. By treaty legislative, administrative and judicial powers may be conferred on organisations established under international law (Article 92). This has been done on many occasions, e.g. on the Benelux, the European Community, the United Nations, the Council of Europe and NATO.