The general rule is that where the parties have embodied the terms of their agreement or contract in a written document as it was done in this case, extrinsic evidence is not admissible to add to, vary, subtract from or contradict the terms of the written instrument: See Mrs. O, D. Layode v Panalpina World Transport NY Ltd (1996) 6 NWLR (pt 456) 544, Glaloye v Balogun (1990) 5 NWLR (pt 148), Union Bank of Nigeria Ltd v Ozigi (1994) 3 NWLR (pt 333) 385.
— J.I. Okoro JSC. B.O. Lewis v. United Bank for Africa Plc. (SC.143/2006, 14 January 2016)