Call to Prayers (Adhaan)
حَدَّثَنَا أَبُو نُعَيْمٍ، قَالَ حَدَّثَنَا ابْنُ عُيَيْنَةَ، عَنْ إِسْحَاقَ، عَنْ أَنَسٍ ـ رضى الله عنه ـ قَالَ صَلَّى النَّبِيُّ صلى الله عليه وسلم فِي بَيْتِ أُمِّ سُلَيْمٍ، فَقُمْتُ وَيَتِيمٌ خَلْفَهُ، وَأُمُّ سُلَيْمٍ خَلْفَنَا.Narrated Anas:The Prophet (ﷺ) prayed in the house of Um Sulaim; and I, along with an orphan stood behind him while Um Sulaim (stood) behind us
From Sahih al-Bukhari, whose reports the scholars accept as authentic.