Rasāʼil al-Kindī al-falsafīyah - Kindī, -approximately 873 (Manshūrāt Maʻhad Tārīkh al-ʻUlūm al-ʻArabīyah wa-al-Islāmīyah. al-Falsafah al-Islāmīyah, 1999)