Ibn Abi Mulaykah (may Allah have mercy on him) said: I wrote to Ibn Abbas (may Allah be pleased with them both) about two girls, one of whom had struck the other, and there was no witness either. He replied: Detain them after Asr, then recite this verse to them: "Indeed, those who exchange the covenant of Allah and their oaths for a small price." [Surah Al Imran: 77] He said: I did so, and she confessed.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الشهادات / 20703