Abu Dawud
Purification (Kitab Al-Taharah)
Book Number: 001 / Hadith Number: 209
Narated By N/A : 'Urwah reported on the authority of his father a tradition from 'All b. Abi Talib who said: I asked al-Miqdad (to consult the Prophet). He then narrated the tradition bearing the same meaning.
Abu Dawud said: This tradition has been reported with another chain of narrators. This version does not mention the word "testicles."