books, and its total number of hadiths reaches (5274). The highest isnāds in Sunan Abū Dāwūd are the quadrilateral chains, in which only four transmitters stand between the author and the Messenger of Allah (peace and blessings be upon him). The collection has been the subject of several commentaries, the most renowned of which is ʿAwn al-Maʿbūd by Abū al-Ṭayyib Shams al-Ḥaqq al-ʿAẓīm Ābādī.