Reference 1 – Ali (as) is Master of all – Books of Ahle Sunnat

Jameel bin Aamir narrates I heard from the Holy Prophet (sawa) that he said on the Day of Ghadeer e Khum “Of Whomsoever I am Master, Ali is his Master”

Reference - al-Bukhari, al-Ta'rikh al-kabir, Haydarabad: Da'irat al-Ma`arif al-`Uthmaniyyah, , 1361-65, Volume 1 Part 1 Page 375