Issues of sub-national referendums regulated at the national level

Tajikistan
Answer
None
Source
Constitutionof Tajikistan
(Adoptedon 6 November 1994, last amended on 22 June 2003)
http://www.president.tj/en/taxonomy/term/5/28
(Official English translation)
Constitutional Law onReferendum
(Enacted in 1995)
http://www.legislationline.org/documents/id/6770
(Official English Translation)