‏فضائل الصحابة‏ : Hadeeth No:6122 This hadith has been transmitted on the authority of Sa'd b. Ibrahim with a slight variation of wording....

‏الأيمان : Hadeeth No:4054 Abu Huraira reported Allaah's Messenger (sallAllaahu alayhi wa sallam) as saying: He who took an oath and (later on) found another thing better than that, he should do that which is better, and expiate for the vow (broken by him)....