Citizenship
Section 309 · 1999 Constitution (2004 edition)
What Constitution says
Notwithstanding the provisions of Chapter III of this Co nstitution but subject to section 28 thereof, any person who became a citizen of Nigeria by birth, registration or naturalisation under the provisions of any other Constitution shall continue to be a citizen of Nigeria under this Constitution.
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 127. Original document
Release: draft-c8d50d87fae9. Source scope, review and corrections