(60) باب وَقْتِ رَكْعَتَىِ الْفَجْرِ وَذِكْرِ الاِخْتِلاَفِ عَلَى نَافِعٍ
It was narrated from Ibn 'Umar that Hafsah, the Mother of the Believers, :
Told him that when the Muaddhin fell silent, Allah's Messenger (ﷺ) would pray two brief rak'ahs. (FR)
Reference (FR): Sunan an-Nasa'i 1772 (FR)
In-book reference (FR): Book 20, Hadith 175 (FR)
English translation (FR): Vol. 2, Book 20, Hadith 1773 (FR)