Sahih al-Bukhari 634

Arabic

حَدَّثَنَا مُحَمَّدُ بْنُ يُوسُفَ، قَالَ حَدَّثَنَا سُفْيَانُ، عَنْ عَوْنِ بْنِ أَبِي جُحَيْفَةَ، عَنْ أَبِيهِ، أَنَّهُ رَأَى بِلاَلاً يُؤَذِّنُ فَجَعَلْتُ أَتَتَبَّعُ فَاهُ هَا هُنَا وَهَا هُنَا بِالأَذَانِ‏.‏

English translation

Narrated `Aun bin Abi Juhaifa:My father said, "I saw Bilal turning his face from side to side while pronouncing the Adhan for the prayer

Reference: Sahih al-Bukhari 634, Book of Call to Prayers (Adhaan). English translation by Dr. Muhammad Muhsin Khan.