Ibn Lahi'ah narrates from Bukayr that he heard Abu Salamah (may Allah have mercy on him) asking the one who has the right for an oath along with one witness. Bukayr said: Abu Salamah (may Allah have mercy on him) kept judging in this way.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الشهادات / 20688