About “Musnad Ishaq ibn Rahwayh”
Musnad Ishaq ibn Rahwayh is one of the oldest hadith books, compiled by Ishaq ibn Rahwayh, who was the teacher of the famous hadith scholars Muhammad al-Bukhari, Muslim ibn al-Hajjaj, al-Tirmidhi, and al-Nasa'i. (Summary adapted from Wikipedia, CC BY-SA 4.0.)
Some summaries adapted from Wikipedia, CC BY-SA 4.0.