Area handbook for Iran
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Dalb, Andrew (1998). Dictionary of Languages: The Definitive Reference to More Than 400 Languages. [S.l.]: Columbia University Press. p.226. ISBN0-231-11568-7
Bilingualism in Mazandaran: Peaceful Coexistence With Persian by Maryam Borjian, Columbia University, Page 66. Online Access: Arquivado em 21 de setembro de 2006, no Wayback Machine.