Musnad Ahmad 30:2834

'Abd al-Rahman narrated to us, he said: Zuhayr narrated to me, from al-'Ala', from his father, from Abu Hurayrah, from the Prophet, may God bless him and grant him peace, who said: "Let not one of you say: 'My male slave' (abdi) and 'my female slave' (amati). All of you are slaves of God, and all of your women are female slaves of God. But let him say: 'My boy' (ghulami), 'my girl' (jariyati), 'my young man' (fataya), and 'my young woman' (fatati)."