Zakat (Kitab Al-Zakat)
Dawud :: Book 9 : Hadith 1642
Narrated Ibn al-Firasi:
Al-Firasi asked the Apostle of Allah (peace_be_upon_him): May I beg, Apostle of Allah? The Prophet (peace_be_upon_him) said: No, but if there is no escape from it, beg from the upright.