Power of the National Assembly as to determination of certain questions
Section 79(a) · 1999 Constitution (2004 edition)
What Constitution says
(a) persons who may apply to an election tribunal for determination of any question as to whether - (i) any person has been validly elected as a member of the Senate or of the House of Representatives, (ii) the term of office of any person has ceased, or (iii) the seat in the Senate or in the House of Representatives of a member of that House has become vacant;
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 51–52. Original document
Release: draft-c8d50d87fae9. Source scope, review and corrections