Musannaf Ibn Abi Shayba 1:1723

1723. Abd al-A’la narrated to us, from Muhammad ibn Ishaq, from al-Zuhri, from Urwah, from Zayd ibn Khalid al-Juhani, who said: The Messenger of Allah (may Allah bless him and grant him peace) said: "Whoever touches his private part, let him perform ablution."