Ethnologue report for language code:mas ethnologue.com, '453,000 in Kenya (1994 I. Larsen BTL) ... 430,000 in Tanzania (1993)', Gordon, Raymond G., Jr. (ed.), 2005. Ethnologue: Languages of the World, Fifteenth edition. Dallas, Tex.: SIL International
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खुल्लर, डी.आर. भूगोल. टाटा मैकग्रा - हिल एज्युकेशन. पृ॰ 9.19-9.20.