Issues in relation to which referendums are optional at the national level

Moldova, Republic of
Constitution of Republic of Moldova
http://aceproject.org/ero-en/regions/europe/MD/the-constitution-of-moldova-2000/at_download/file
Article 141.
Initiativefor revising the Constitution
(1) Arevision of the Constitution may be initiated by:
(a) a numberof at least 200,000 voting citizens of the Republic of Moldova. Citizensinitiating the revision of the Constitutionmust cover at least a half of the territorial-administrative units of thesecond level, and in each of these units must beregistered at least 20000 signatures in support of the said initiative;
(b) a numberof at least a third of the Parliament members;
(c) theGovernment.
(2)Constitutional law drafts shall be submitted to Parliament only alongside withthe Constitutional Court advisory opinion adopted by a vote of atleast 4 judges.
Article 142.
Limitsof revision
(1)The provisions regarding the sovereignty, independence and unity of the State,as well as those regarding the permanent neutrality of the State may be revisedonly by referendum based on a majorityvote of the registered voting citizens.
(2)No revision shall be performed, if it implies the infringement of fundamentalrights and freedoms of citizens, or their guarantees.
(3)The Constitution may not be revised under a state of national emergency,martial law or war.
Article 143.
Lawon the Constitutional Amendment
(1)Parliament shall be entitled to pass a law on the amendment of Constitutionfollowing at least 6 months from the date of the corresponding initiativelaunch. The law shall be adopted by a vote of two-thirds of the Parliamentmembers.
(2)If, within a year from the date when the initiative on the amendment ofConstitution was launched, the Parliament has not passed the appropriateconstitutional law, the proposal shall be deemed null and void.
Parts of the constitution that are not covered by the Article 142, can be put to a referendum.