Parliament, and then: either passed again after at least three months under the same terms, or passed on the referendum, if a referendum is requested in first two months of the three-month period by either one quarter of members of the Parliament or 25 thousand registered voters. The referendum on constitutional amendment (defined in Article 114) is binding. Referendums in general (defined in Article 51) are not explicitly stated to be binding. The general framework of the organizational arrangements of referendums is established by "The Act of 4 February 2005 on the national referendum". There were four referendums in Luxembourg since 1919: the referendum on head of state and economic union in 1919 the referendum on banning the Communist party in 1937 European Constitution referendum in 2005 Luxembourg constitutional referendum in 2015 None of the referendums were constitutional amendments, so were non-binding. See also Electoral calendar Electoral system Footnotes Further reading External links Luxembourg at Adam Carr's Election Archive Luxembourg at Parties and Elections