He also referred to it in volume 6 of Silsilat al-Aḥādīth al-Ṣaḥīḥa, hadith no. 2616, p. 227.

( … ) “Index of Some Hadith Manuscripts in the Ẓāhiriyyah Library, Damascus” = “Selections from Hadith Manuscripts.”

( … ) “Index of the Companion Narrators in the Musnad of Imām Aḥmad ibn Ḥanbal” = “Index of the Companions’ Musnads.”

“The Comprehensive Index of the Hadiths and Reports in al-Kāmil,” by Ibn ʿAdī, [authored].

“Index of the book al-Kawākib al-Darārī by Ibn ʿUrwah al-Ḥanbalī, and the titles of the works quoted therein,” [authored]—it is now lost.

“Index of the Hadith Manuscripts in the Awqāf Library, Aleppo,” [authored].

( … ) “Index of the Manuscripts in Dār al-Kutub al-Ẓāhiriyyah” = “Selections from Hadith Manuscripts.”

“Index of the Companions’ Musnads for the Musnad of Imām Aḥmad,” [authored]—(printed).

“The Selected Index from the Ibn Yūsuf Library,” Marrakesh, [authored].

Al-Aṣālah records:

(The Shaykh—may Allah preserve him—has many such indexes, whether for hadith collections or for biographical works. He compiled them long ago to make research and cross-checking easier for himself, and I was unable to list them all.) End quote.

I say: The Shaykh’s lifelong immersion in hadith literature—reading, researching, and studying—led him to prepare these indexes so that he could reach his goal with ease, for most books in those days lacked the kind of indexing available now.

Today, with the advent of multimedia technology, we can search for a hadith in hundreds of works, a thousand volumes, stored on a single disc, in scarcely a minute either way.

There is no doubt that these indexes and electronic aids are merely guides to the books; they can never replace direct reliance on the original works, and that is well known.

“al-Qāʾid ilā Taṣḥīḥ al-ʿAqāʾid,” by al-Muʿallimī, [verification and commentary in collaboration with Shaykh ʿAbd al-Razzāq Ḥamzah]—(printed).

This work is an excerpt from al-Muʿallimī’s major compendium al-Tankīl. The publisher, Zuhayr al-Shāwīsh—may Allah preserve him—issued it separately because of its importance and because its subject matter is unrelated to al-Tankīl.

I only wish he had mentioned this in the introduction to al-Qāʾid.