(15) باب فَضْلِ السُّنَنِ الرَّاتِبَةِ قَبْلَ الْفَرَائِضِ وَبَعْدَهُنَّ وَبَيَانِ عَدَدِهِنَّ
Nu'man b. Salim reported with the same chain of transmitters:
He who observed twelve voluntary rak'ahs, a house will be built for him in Paradise.
Reference: Sahih Muslim 728 b
In-book reference: Book 6, Hadith 125
USC-MSA web (English) reference(deprecated numbering scheme): Book 4, Hadith 1580