Ahmad al-Musallam al-Mousilî and al-Durr al-Nakî fî Ilm al-Mûsikî. The personalityof Ahmad al-Musallam al-Mousilî is unknown. The origin of his al-Durr al-Nakî fî Ilm al-Mûsikîwas written by Abd al-Mumin al-Balkhî in Persian language and it was translated into Arabic byal-Mousilî. The original title of al-Balkhî was Bayân al-Maqâmat al-Aliyya Maa al-Furûi wa alAwzân al-Asliyya. Al-Mousýlî wished to name his translation al-Durr al-Nakî because of his extrasignificant information. Some of the scholars thought wrongly that al-Balkhî is Safî al-Dîn Abdal-Mumin al-Urmawî thereby this treatise was quoted from works of Safî al-Dîn especially fromhis al-Risâla al-Sharafiyya. In this study al-Durr al-Nakî was translated into Turkish and indicatedthis wrong