https://abukhadeejah.com/ahmad-b-hanbal-usool-as-sunnah-straight-path-sirat-mustaqeem-intro/
Introduction: The Sirātul-Mustaqeem and the Path of the Salaf: Imām Ahmad bin Hanbal’s Usūl As-Sunnah (The Foundations of the Sunnah) with the explanation of Shaikh An-Najmi.