Analysis of information sources in references of the Wikipedia article "Ubaydallah ibn al-Sari" in English language version.
However, the people of Zuṭṭ origin were not totally obscure in the social life. Some of them climbed in the social scale during the 'Abbāsid period in 'Iraq. For instance, "al-Sari b. al-Hakam b. Yusuf al-Zutti" was a governor of Egypt in 200 – 205 H./815 – 820 A.D.
Many of them [Zutt] are even said to have risen to high rank, e.g. al-Sarī b. al-Hakam b. Yūsuf al-Zuṭṭī, governor of Egypt (200 – 5/816 – 21).