Divination and Omens (Kitab Al-Kahanah Wa Al-Tatayyur)
Dawud :: Book 29 : Hadith 3915
Narrated Abdullah ibn Amr ibn al-'As:
The Prophet (peace_be_upon_him) said: A slave who has entered into an agreement to purchase his freedom is a slave as long as a dirham of the agreed price remains to be paid.