Sunan an-Nasa'i 2511
سنن النسائي#2511SahihIt was narrated that Abu Sa'eed Al-Khudri said:"The Messenger of Allah enjoined Sadaqatul Fitr, a Sa' of barley or a Sa of dates or a Sa' of cottage cheese
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Abu GhuddahHasan Sahih
Al-AlbaniHasan Sahih
Zubair Ali ZaiSahih - Agreed Upon
In-book reference: 23:77