Direct election and franchise (House of Assembly)
Section 117(2) · 1999 Constitution (2004 edition)
What Constitution says
(2) Every citizen of Nigeria, who has attained the age of eighteen years residing in Nigeria at the time of the registration of voters for purposes of election to any legislative house, shall be entitled to be registered as a voter for that election.
This is the 1999 Constitution as published in 2004. Later amendments aren't included yet, so a section may have changed since.
Original source
Official Gazette · CFRN 1999 official PDF · printed page 62. Original document
Release: draft-c8d50d87fae9. Source scope, review and corrections