Malik related to me from Rabia ibn Abi Abd ar-Rahman that a manin the time of Aban ibn Uthman's amirate freed all of his slaves anddid not have other property than them. Aban ibn Uthman took charge ofthe slaves and they were divided into three groups. Then he drew lotson the basis that which ever group drew the dead man's arrow would befree. The arrow fell to one of the thirds, and that third was freed.
USC-MSA web (English) reference: Book 38, Hadith 4
Arabic reference: Book 38, Hadith 1469