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Aḥmad b. Ḥanbal (d. 855 CE) - al-Jāmiʿ li-ʿulūm imām Aḥmad: al-Rijāl - أحمد بن حنبل - الجامع لعلوم إمام أحمد: الرجال
First published in 2009, this reference collects the utterances and statements of Aḥmad b. Ḥanbal regarding the Companions and the transmitters of hadith.