سُنَنُ النَّسَائِيِّ
Sunan an-Nasa’i 1004
The Book of the Commencement of the Prayer
Reciting two surahs in one rak'ah
أَخْبَرَنَا إِسْحَاقُ بْنُ إِبْرَاهِيمَ، قَالَ أَنْبَأَنَا عِيسَى بْنُ يُونُسَ، عَنِ الأَعْمَشِ، عَنْ شَقِيقٍ، عَنْ عَبْدِ اللَّهِ، قَالَ إِنِّي لأَعْرِفُ النَّظَائِرَ الَّتِي كَانَ يَقْرَأُ بِهِنَّ رَسُولُ اللَّهِ صلى الله عليه وسلم عِشْرِينَ سُورَةً فِي عَشْرِ رَكَعَاتٍ ثُمَّ أَخَذَ بِيَدِ عَلْقَمَةَ فَدَخَلَ ثُمَّ خَرَجَ إِلَيْنَا عَلْقَمَةُ فَسَأَلْنَاهُ فَأَخْبَرَنَا بِهِنَّ .
It was narrated that 'Abdullah said: I know the similar surahs that the Messenger of Allah (ﷺ) used to recite, twenty surahs in ten rak'ahs." Then he took 'Alqamah's hand and went in, then 'Alqamah came out and we asked him and he told us what they were.
Sunan an-Nasa'i, 1004Sahih (Darussalam)