Discharge of functions of Governor
Section 191(3) · 1999 Constitution (2004 edition)
What Constitution says
(3) Where the office of the Deputy Governor becomes vacant - (a) by reason of death, resignation, impeachment, permanent incapacity or removal in accordance with section 188 or 189 of this Constitution; (b) by his assumption of the office of Governor of a State in accordance with subsection (1) of this section; or (c) for any other reason, the Governor shall nominate and with the approval of the House of Assembly of the State, appoint a new Deputy Governor.
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 89. Original document
Release: draft-c8d50d87fae9. Source scope, review and corrections