مُسْنَدُ أَحْمَدَ
Musnad Ahmad 2499
Musnad of 'Abdullah bin al-'Abbas bin 'Abdul-Muttalib from the Prophet
It was narrated that al-Mas'oodi said: We have never seen anyone who was a greater supporter of the Shi'i view than ‘Adiyy bin Thabit.
Musnad Ahmad 2511This is a report from al-Mas'oodi]