Jami` at-Tirmidhi, Book 2, Hadith 193 (In-Book) ⓘ
Ibn Umar said: "They were bowing during the Subh (Fajr) Prayer."
حَدَّثَنَا هَنَّادٌ، حَدَّثَنَا وَكِيعٌ، عَنْ سُفْيَانَ، عَنْ عَبْدِ اللَّهِ بْنِ دِينَارٍ، عَنِ ابْنِ عُمَرَ، قَالَ كَانُوا رُكُوعًا فِي صَلاَةِ الصُّبْحِ . قَالَ أَبُو عِيسَى وَحَدِيثُ ابْنِ عُمَرَ حَدِيثٌ صَحِيحٌ .
also referenced under: Hadith 341 (Reference) & Volume 1, Book 2, Hadith 341 (DarusSalam)