Abu Dawud said: Sa'id b. Bashir reported this tradition in a like manner, except that he narrated "one mudd or half mudd" (instead of sa'). He narrated it from Samurah.
Abu Dawud said: I heard Ahmad bin Hanbal being asked about the differences over the narration of this Hadith. He said: "Hammam has a stronger memory - in my opinion - than Ayyub."
In-book : Book 2, Hadith 665
English translation : Book 3, Hadith 1049