(60) باب وَقْتِ رَكْعَتَىِ الْفَجْرِ وَذِكْرِ الاِخْتِلاَفِ عَلَى نَافِعٍ
It was narrated from Ibn Umar that Hafsah said:
"When dawn came, the Messenger of Allah (ﷺ) would not pray anything but two brief rak'ahs." (ID)
Reference (ID): Sunan an-Nasa'i 1776 (ID)
In-book reference (ID): Book 20, Hadith 179 (ID)
English translation (ID): Vol. 2, Book 20, Hadith 1777 (ID)