Muwatta Malik 1021
موطأ مالك#1021SahihYahya related to me from Malik from Nafi that Abdullah ibn Umar said, "If someone breaks an oath which he has stressed, he has to free a slave, or clothe ten poor people. If someone breaks an oath, but has not stressed it, he only has to feed ten poor people and each poor person is fed a mudd of wheat. Some one who does not have the means for that, should fast for three days
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Salim al-HilaliMauquf Sahih
In-book reference: 22:8