Ahmed b. Ali b. Müsenna

His patronymic is Abū Yaʿlā. He was from Mosul. He is the author of the famous "Musnad." He heard hadith from Imam Ahmad b. Hanbal and from hadith scholars of his generation. He was an eminent hadith ḥāfiẓ (memorizor and master of hadith). He authored well-organized works. In his transmissions, he was upright and his retention was reliable.