Muwaththa' Malik · #866
وَحَدَّثَنِي يَحْيَى، عَنْ مَالِكٍ، عَنْ جَعْفَرِ بْنِ مُحَمَّدٍ، عَنْ أَبِيهِ، عَنْ عَلِيِّ بْنِ أَبِي طَالِبٍ، كَانَ يَقُولُ {مَا اسْتَيْسَرَ مِنَ الْهَدْىِ} شَاةٌ .
English
Yahya related to me from Malik from Jafar ibn Muhammad from his father that Ali ibn Abi Talib used to say, "The least difficult thing acceptable as a sacrificial animal is a sheep