أَخْبَرَنَا إِسْمَاعِيلُ بْنُ مَسْعُودٍ، قَالَ حَدَّثَنَا بِشْرُ بْنُ الْمُفَضَّلِ، عَنْ يُونُسَ، عَنِ ابْنِ سِيرِينَ، قَالَ حَدَّثَنِي بَعْضُ، مَنْ صَلَّى مَعَ رَسُولِ اللَّهِ صلى الله عليه وسلم صَلاَةَ الصُّبْحِ فَلَمَّا قَالَ " سَمِعَ اللَّهُ لِمَنْ حَمِدَهُ " . فِي الرَّكْعَةِ الثَّانِيَةِ قَامَ هُنَيْهَةً .
It was narrated that Ibn Sirin said: "Some of those who prayed the Subh prayer with the Messenger of Allah (PBUH) narrated to me that when he said: Sami'Allahu liman hamidah (Allah hears those who praise Him)' in the second rak'ah, he stood for a while." Translation Not Available
Book Ref: Sunan An Nisai Book 12 Hadith 1072
Web Ref: Sunan An Nisai Vol 2 Book 12 Hadith 1073