Who can initiate an optional referendum at the national level?

Turkmenistan
- President
- Legislative majority
- Registered electors
Constitution 2008
http://legislationline.org/documents/section/constitutions/country/51
Article 53: The President of Turkmenistan:
[...]
9) Designates the date of the referendum, has theright to convene an early session of the Mejlis;
Article 63: Mejlis:
[...]
5) Determines whetherto hold national referendums;
Article 95: The right to conduct national referendum belongs tothe Mejlis of Turkmenistan on proposal of at least two-third of its establisheddeputies, or on the petition of no less than 250000 eligible voters.