 Complete the following phrase:  The Third Amendment, passed in 1972, allowed Ireland to accede to the European Communities. In 1986, the government signed the Single European Act SEA. However, Raymond Crotty sought an injunction against ratification by the state. In Crotty v. An Taoiseach 1987, the Supreme Court held that the further transfer of powers from the state to the European institutions within the SEA was not necessitated by the obligations of membership of the Communities as provided for by the Third Amendment. Consequently, the Constitution required further amendment, before the SEA could be ratified. This was done in a referendum later in 1987. On the same basis, further referendums on European Treaties were held on the Maastricht Treaty in 1992, on the Amsterdam Treaty in 1998, on the Nice Treaty in 2001 and in 2002, and on the Lisbon Treaty 