Observing Saum (fast) on Tashriq days. Sahih al-Bukhari 1996

Arabic hadith text
وَقَالَ لِي مُحَمَّدُ بْنُ الْمُثَنَّى حَدَّثَنَا يَحْيَى، عَنْ هِشَامٍ، قَالَ أَخْبَرَنِي أَبِي كَانَتْ، عَائِشَةُ ـ رضى الله عنها ـ تَصُومُ أَيَّامَ مِنًى، وَكَانَ أَبُوهَا يَصُومُهَا‏.‏
Translation
Narrated Yahya

Hisham said, "My father said that 'Aishah (ra) used to observe Saum (fast) on the days of Mina." His (i.e., Hisham's) father also used to observe Saum on those days.