Hadith 13:12
Narrated 'Uqba bin 'Aamir (RA):
Allah's Mssenger (ﷺ) said: "The atonement for a vow (Nadhr) is (the same as) the atonement an oath (Yamin)." [Reported by Muslim]. at-Tirmidhi added, "If he did not specify it." [And he graded it Sahih (authentic)].
وَعَنْ عُقْبَةَ بْنِ عَامِرٍ - رضى الله عنه - قَالَ: قَالَ رَسُولُ اَللَّهِ - صلى الله عليه وسلم -{ "كَفَّارَةُ اَلنَّذْرِ كَفَّارَةُ يَمِينٍ" } رَوَاهُ مُسْلِمٌ وَزَادَ اَلتِّرْمِذِيُّ فِيهِ: { إِذَا لَمْ يُسَمِّ } , وَصَحَّحَهُ.
Original Reference: Bulugh al-Maram 1385