al-Hakim al-Naysaburi

Abu Abd Allah Muhammad ibn Abd Allah ibn Muhammad al-Hakim al-Naysaburi al-Shafi'i was the leading hadith scholar of Khorasan in the 4th century AH. His major work al-Mustadrak 'ala al-Sahihayn (The Supplement to the Two Sahihs) contains approximately 9,000 hadiths which he claimed met al-Bukhari's or Muslim's criteria but were not included in their collections. Al-Dhahabi abridged it with critical comments. He also wrote Ma'rifat 'Ulum al-Hadith (an important work on hadith sciences), al-Amali, and a biography of al-Shafi'i. He served as chief judge (qadi) of Nishapur. He died in 405 AH.