كتاب 10
10  
Book 10
(10)
Chapter 10
(10)
باب 10
Sahih al-Bukhari 589
Narrated Anas:
The people mentioned the fire and the bell (they suggested those as signals to indicate the starting of prayers), and by that they mentioned the Jews and the Christians. Then Bilal was ordered to pronounce Adhan for the prayer by saying its wordings twice, and for the Iqama (the call for the actual standing for the prayers in rows) by saying its wordings once. (Iqama is pronounced when the people are ready for the prayer).
حَدَّثَنَا عِمْرَانُ بْنُ مَيْسَرَةَ، حَدَّثَنَا عَبْدُ الْوَارِثِ، حَدَّثَنَا خَالِدٌ الْحَذَّاءُ، عَنْ أَبِي قِلاَبَةَ، عَنْ أَنَسٍ، قَالَ ذَكَرُوا النَّارَ وَالنَّاقُوسَ، فَذَكَرُوا الْيَهُودَ وَالنَّصَارَى، فَأُمِرَ بِلاَلٌ أَنْ يَشْفَعَ الأَذَانَ وَأَنْ يُوتِرَ الإِقَامَةَ‏.‏
Reference : Sahih al-Bukhari 589
In-book reference : Book 10, Hadith 589
USC-MSA web (English) reference : Vol. 1, Book 1, Hadith 589
  (deprecated numbering scheme)