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 language 

Some noteworthy (and quite convincing) work has been done by Alexander Vovin that suggests that the Xiongnu spoke a Yeniseian language similar to Ket. This is definitely worth mentioning on the page.

Vovin, Alexander. ""Did the Xiongnu speak a Yeniseian language?"". Central Asiatic Journal 44/1 (2000), pp. 87-104.

-Andrew"