Sahih Muslim
The Book of Pilgrimage (Kitab Al-Hajj)
Book Number: 007 / Hadith Number: 3019
'All (Allah be pleased with him) reperted: Allah's Messenger (may peace be upon him) put me in charge of his sacrificial animals, that I should give their flesh. skins and saddle cloths as sadaqa, but not to give anything to the butcher, saying: We would pay him ourselves.