Issues in relation to which referendums are mandatory 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
Article142.
Limitsof revision
(1)The provisions regarding the sovereignty, independence and unity of the State,as well as those regarding the permanent neutrality of theState may be revised only by referendum based on a majority vote of theregistered 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.