(5) باب صَاعِ الْمَدِينَة
Narrated Al-Ju'aid bin `Abdur-Rahman:
As-Sa'ib bin Yazid said, "The Sa' at the time of the Prophet (ﷺ) was equal to one Mudd plus one-third of a Mudd of your time, and then it was increased in the time of Caliph `Umar bin `Abdul `Aziz."
Reference: Sahih al-Bukhari 6712
In-book reference: Book 84, Hadith 5
USC-MSA web (English) reference(deprecated numbering scheme): Vol. 8, Book 79, Hadith 703