Afro-Asiatic Hausa
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Ethnologue Report for Hausa - Information about where Hausa is spoken and the number of its speakers.
Hausa Language - Wikipedia article.
The Hausa Language - by Paul Newman - Write-up on a reference grammar of the Hausa language, by one of the top authorities in the field, and published by Yale University Press.
Hausa Words - Vocabulary words and phrases.
Teach Yourself Hausa - Introduction to the Hausa language, including the basics of its phonetics and grammar, and some sample sentences illustrating everyday conversation in the language.
UCLA Hausa Page - UCLA resource guide to the Hausa language and the culture of Hause speakers. Includes an online Hausa grammar. Help build the largest human-edited directory on the web.