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Bosworth, C.E. (1988). "BĀḎḠĪS". In Yarshater, Ehsan (ed.). Encyclopædia Iranica, Volume III/4: Bačča(-ye) Saqqā–Bahai Faith III. London and New York: Routledge & Kegan Paul. pp. 370–372. ISBN978-0-71009-116-1.