Legal provisions for mandatory referendums at national level

Mauritius
Constitutionof Mauritius
(1968),
http://www.gov.mu/portal/site/AssemblySite/menuitem.ee3d58b2c32c60451251701065c521ca/
Article47(3). A Bill for an Act of Parliament to alter the provisions of section 1 or57(2) shall not be passed by the Assembly unless – (a) the proposed Bill hasbefore its introduction in the Assembly been submitted, by referendum, to theelectorate of Mauritius and has been approved by the votes of not less thanthree quarters of the electorate.