Legal provisions for optional referendums at national level

Mongolia
Article Twenty five
1. The State Ikh Khural may consider on itsinitiative any issue pertaining to domestic and foreign policies of the State,and shall keep within its exclusive power the following issues and decidethereon:
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16) to hold national referenda. To verify thevalidity of a referendum in which the majority of citizens eligible forelection has taken parts, and to abide by and give effect to the decision whichhas obtained a majority of votes;
Article Sixty eight
1. Amendments to the Constitution shall be initiated by organization and officials enjoying the right to legislative initiative and could be submitted by the Constitutional court to the State IkhKhural.
2. A national referendum on constitutional amendment may be held on the concurrence of not less than two thirds of the members of the State Ikh Khural. The referendum shall be held in accordance with the provisions of sub-paragraph 16 of Paragraph 1, Article 25 of the Constitution.