Muwatta Malik, Book 3, Hadith 35 (USC-MSA)

Yahya related to me from Malik from Hisham ibn Urwa from his father that Abu Bakr as-Siddiq prayed subh and recited suratal-Baqara in the two rak'as.

حَدَّثَنِي يَحْيَى، عَنْ مَالِكٍ، عَنْ هِشَامِ بْنِ عُرْوَةَ، عَنْ أَبِيهِ، أَنَّ أَبَا بَكْرٍ الصِّدِّيقَ، صَلَّى الصُّبْحَ فَقَرَأَ فِيهَا سُورَةَ الْبَقَرَةِ فِي الرَّكْعَتَيْنِ كِلْتَيْهِمَا ‏.‏

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also referenced under: Book 3, Hadith 182 (In-Book)