Legal provisions for mandatory referendums at national level

Hungary
Hungary'sConstitution of 2011
https://www.constituteproject.org/constitution/Hungary_2011.pdf
National referenda
Article 8
1. Parliament shall order a national referendum upon the motion of atleast two hundred thousand electors. Parliament may order a national referendumupon the motion of the President of the Republic, the Government or one hundredthousand electors. The decision made by any valid and conclusive referendumshall be binding on Parliament.
2. National referenda may be held about any matter within Parliament’s responsibilitiesand competences.
3. No national referendum may be held on:
a. any matter aimed at the amendment of the Fundamental Law,
b. the contents of the Acts on the State Budget and its implementation,the central tax type, pension or healthcare contributions, customs and thecentral conditions for local taxes,
c. the contents of the Acts on the elections of Members of Parliament,local representatives and mayors, and members of the European Parliament,
d. any obligation arising from an international agreement,
e. any matter related to human resources and the establishment oforganisations within the competence of Parliament,
f. the voluntary dissolution of Parliament,
g. the mandatory dissolution of any representative body,
h. the declaration of a state of war, state of national crisis and stateof emergency, and on the declaration or extension of a state of preventivedefence,
i. any matter related to participation in military operations,
j. the granting of pardons.
4. A national referendum shall be valid if more than half of allelectors have cast a valid vote, and shall be conclusive if more than half ofall voters casting a valid vote have given the same answer to a question.