Issues of sub-national referendums regulated at the national level

Nigeria
Constitution of the Federal Republic of Nigeria 1999
(Adopted in 1999, last amended in 2011)
(Mandatory Referendum)
Article 8.
(1) An Act of the NationalAssembly for the purpose of creating a new State shall only be passed if-
(b)[?] a proposal for thecreation of the State is thereafter approved in a referendum by at leasttwo-thirds majority of the people of the area where the demand for creation ofthe State originated;
(c) the result of the referendumis then approved by a simple majority of all the States of the Federationsupported by a simple majority of members of the Houses of Assembly; [?]
Article 8.
(3) A bill for a Law of a House ofAssembly for the purpose of creating a new local government area shall only bepassed if -
(b) [?]a proposal for thecreation of the local government area is thereafter approved in a referendum byat least two-thirds majority of the people of the local government area wherethe demand for the proposed local government area originated;
(c) theresult of the referendum is then approved by a simple majority of the membersin each local government council in a majority of all the local governmentcouncils in the State; and[?]
Referendums on the creation of anew state and the creation of a new local government are governed by theIndependent National Election Commission and take place at the sub-nationalarea in which it is demanded.