Direct election and franchise (National Assembly)
Section 77(1) · 1999 Constitution (2004 edition)
What Constitution says
(1) Subject to the provisions of this Constitution, every Senatorial district or Federal constituency established in accordance with the provisions of this Part of this Chapter shall return a member who shall be directly elected to the Senate or the House of Representatives in such manner as may be prescribed by an act of the National Assembly.
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 51. Original document
Release: draft-c8d50d87fae9. Source scope, review and corrections