The Book of Prayers (Kitab Al-Salat)

Muslim :: Book 4 : Hadith 1471

Yahya b. Yazid al-Huna'i reported: I asked Anas b. Malik about shortening of prayer. He said: When the Messenger of' Allah (may peace be upon him) had covered a distance of three miles or three farsakh (Shu'ba, one of the narrators, had some doubt about it) he observed two rak'ahs.

Source materials are from the University of Southern California MSA site
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