R. Niger

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By Hel-hama - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=27632291

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R. Benue

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By Kmusser - Own work, Elevation data from SRTM, drainage basin from GTOPO [1], all other features from Vector Map., CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=9896070

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Linguistic map

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