https://abukhadeejah.com/ahmad-hanbal-usool-sunnah-innovations-hizbiyyah-differing-sectarianism-call-to-unity-part-3/
Part 3: To Abandon Innovations, Hizbiyyah (Partisanship), Differing, Sectarianism, and Establishing the Call to Unity: Imām Ahmad bin Hanbal’s Usūl As-Sunnah (The Foundations of the Sunnah) with the explanation of Shaikh An-Najmi.