Hammad bin Usamah حماد بن أسامة - أبو أسامة · The Book of the Etiquette of Judges

"There were two female neighbors who used to do leatherwork (with an awl) in At-Ta'if. One of them came out with her hand bleeding and claimed that her companion had injured her, but the other one denied it. I wrote to Ibn 'Abbas concerning that. He wrote, (saying) that the Messenger of Allah ruled that the person against whom the claim was made should swear an oath. For if people were to be given what they claimed was theirs, then…