"Whoever narrated to you that the Prophet would urinate while standing; then do not believe him. He would not urinate except while squatting." [He said:] There are narrations on this topic from Umar, Buraidah, [and Abdur-Rahman bin Hasanah].
Reference: Jami` at-Tirmidhi 12 In-book : Book 1, Hadith 12 English translation : Vol. 1, Book 1, Hadith 12
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