Sunan Ibn Majah, Chapter: The Chapters of Purification and its Sunnah

"The Messenger of Allah (saw) forbade us to urinate while standing." (Daif) I heard Muhammad (SAW) bin Yazid, Abu Abdullah,*say: "I heard Ahmad bin Abdur-Rahman Al-Makhzumi say: Sufyan Ath-Thawri said concerning the Hadith of Aishah - 'I (always) saw him urinating whilst sitting down' - a man knows more about that (about such matters) than she.' Ahmad bin Abdur-Rahman said: 'It was the custom of the Arabs to urinate while standing up. Do you not see that in the Hadith of Abdur-Rahman bin Hasanah it was said: 'He sits down to urinate as a woman does.'"** *That is, Ibn Majah. **See no. 346.