Sahih al-Bukhari 4507
Narrated Salama:
When the Divine Revelation: 
"For those who can fast, they had a choice either fast, or feed a poor for every day," (2.184) was 
revealed, it was permissible for one to give a ransom and give up fasting, till the Verse succeeding it 
was revealed and abrogated it.
حَدَّثَنَا قُتَيْبَةُ، حَدَّثَنَا بَكْرُ بْنُ مُضَرَ، عَنْ عَمْرِو بْنِ الْحَارِثِ، عَنْ بُكَيْرِ بْنِ عَبْدِ اللَّهِ، عَنْ يَزِيدَ، مَوْلَى سَلَمَةَ بْنِ الأَكْوَعِ عَنْ سَلَمَةَ، قَالَ لَمَّا نَزَلَتْ ‏{‏وَعَلَى الَّذِينَ يُطِيقُونَهُ فِدْيَةٌ طَعَامُ مِسْكِينٍ‏}‏ كَانَ مَنْ أَرَادَ أَنْ يُفْطِرَ وَيَفْتَدِيَ حَتَّى نَزَلَتِ الآيَةُ الَّتِي بَعْدَهَا فَنَسَخَتْهَا‏.‏ مَاتَ بُكَيْرٌ قَبْلَ يَزِيدَ‏.‏