is the Musnad of Imām Aḥmad.

• al-sunan: a collection in which the ḥadīths are arranged according to the chapters of jurisprudence; for example, Sunan Abū Dāwūd.

• al-muʿjam: a work in which the reports are ordered according to the shaykhs, either alphabetically, by the date of each shaykh’s death, or by some other scheme; such as al-Ṭabarānī’s three Muʿjams.

• al-mustadrak: a compilation that gathers narrations missed by the author of another book, adhering to that author’s own criteria; for instance, al-Ḥākim’s Mustadrak on the Two Ṣaḥīḥs.

• al-mustakhraj: a work whose compiler takes one of the canonical Ṣaḥīḥ collections and re-narrates its contents with his own chains of transmission that do not pass through the original author; such as al-Ismāʿīlī’s Mustakhraj on Ṣaḥīḥ al-Bukhārī.

• al-ʿilal: a book that assembles defective reports and explains the flaws in each; for example, the ʿIlal of al-Dāraqutnī and the ʿIlal of al-Tirmidhī.

• al-juzʾ: a booklet devoted either to all the narrations of a single transmitter or to a single legal issue; e.g., al-Bukhārī’s tract “Recitation Behind the Imām.”

• al-arbaʿūn: a compilation that gathers forty ḥadīths on a single topic—or on various topics. The most famous example is al-Nawawī’s Forty.

Those whose ḥadīths the author cites in Bulūgh al-Marām:
1 – Imām Abū ʿAbdillāh Aḥmad ibn Muḥammad ibn Ḥanbal al-Shaybānī al-Baghdādī, one of the four great imams, d. 241 AH.
2 – Imām Abū ʿAbdillāh Muḥammad ibn Ismāʿīl al-Bukhārī al-Juʿfī, compiler of the Ṣaḥīḥ, d. 256 AH.
3 – Imām Abū al-Ḥusayn Muslim ibn al-Ḥajjāj al-Qushayrī al-Naysābūrī, affiliated with one of—