Volume 1, Book 4, Number 146: Narrated Abu Aiyub Al-Ansari: Allah's Apostle said, "If anyone of you goes to an open space...
Volume 1, Book 4, Number 146:
Narrated Abu Aiyub Al-Ansari:
Allah's Apostle said, "If anyone of you goes to an open space for answering the call of nature he should neither face nor turn his back towards the Qibla; he should either face the east or the west."
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http://www.holyebooks.org/islam/hadith_of_bukhari/004.sbt.html
