كتاب الإيمان
1  
The Book of Faith
(86)
Chapter: The Prophet (saws) will defer his supplication in order to intercede for his ummah
(86)
باب اخْتِبَاءِ النَّبِيِّ صلى الله عليه وسلم دَعْوَةَ الشَّفَاعَةِ لأُمَّتِهِ ‏‏
Sahih Muslim 201

Abu Zubair heard Jabir b. Abdullah reporting it from the Messenger of Allah (ﷺ):

For every apostle was a prayer with which he prayed (to his Lord) for his Ummah, but I have reserved my prayer for the intercession of my Ummah on the Day of Resurrection.
وَحَدَّثَنِي مُحَمَّدُ بْنُ أَحْمَدَ بْنِ أَبِي خَلَفٍ، حَدَّثَنَا رَوْحٌ، حَدَّثَنَا ابْنُ جُرَيْجٍ، قَالَ أَخْبَرَنِي أَبُو الزُّبَيْرِ، أَنَّهُ سَمِعَ جَابِرَ بْنَ عَبْدِ اللَّهِ، يَقُولُ عَنِ النَّبِيِّ صلى الله عليه وسلم ‏ "‏ لِكُلِّ نَبِيٍّ دَعْوَةٌ قَدْ دَعَا بِهَا فِي أُمَّتِهِ وَخَبَأْتُ دَعْوَتِي شَفَاعَةً لأُمَّتِي يَوْمَ الْقِيَامَةِ ‏"‏ ‏.‏
Reference : Sahih Muslim 201
In-book reference : Book 1, Hadith 404
USC-MSA web (English) reference : Book 1, Hadith 396
  (deprecated numbering scheme)