Expiation for Unfulfilled Oaths
حَدَّثَنَا عَبْدُ اللَّهِ بْنُ يُوسُفَ، أَخْبَرَنَا مَالِكٌ، عَنْ إِسْحَاقَ بْنِ عَبْدِ اللَّهِ بْنِ أَبِي طَلْحَةَ، عَنْ أَنَسِ بْنِ مَالِكٍ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ " اللَّهُمَّ بَارِكْ لَهُمْ فِي مِكْيَالِهِمْ وَصَاعِهِمْ وَمُدِّهِمْ ".Narrated Anas bin Malik:Allah's Messenger (ﷺ) said, "O Allah! Bestow Your Blessings on their measures, Sa' and Mudd (i.e., of the people of Medina)
From Sahih al-Bukhari, whose reports the scholars accept as authentic.