Call to Prayers (Adhaan)

Bukhari :: Book 1 :: Volume 11 :: Hadith 579

Narrated Anas:

Bilal was ordered to repeat the wording of the Adhan for prayers twice, and to pronounce the wording of the Iqamas once except "Qad-qamat-is-Salat".

Source materials are from the University of Southern California MSA site
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