Sahih al-Bukhari 619
Book 10: Call to Prayers (Adhaan) · Narrated by `Aisha
Arabic
حَدَّثَنَا أَبُو نُعَيْمٍ، قَالَ حَدَّثَنَا شَيْبَانُ، عَنْ يَحْيَى، عَنْ أَبِي سَلَمَةَ، عَنْ عَائِشَةَ، كَانَ النَّبِيُّ صلى الله عليه وسلم يُصَلِّي رَكْعَتَيْنِ خَفِيفَتَيْنِ بَيْنَ النِّدَاءِ وَالإِقَامَةِ مِنْ صَلاَةِ الصُّبْحِ.
English translation
Narrated `Aisha:The Prophet (ﷺ) used to offer two light rak`at between the Adhan and the Iqama of the Fajr prayer
Reference: Sahih al-Bukhari 619, Book of Call to Prayers (Adhaan). English translation by Dr. Muhammad Muhsin Khan.