Sunan Ibn Majah
1140
Sahih+2

It was narrated that ‘Aishah said:“The Messenger of Allah (ﷺ) said: ‘Whoever persists in performing twelve Rak’ah from the Sunnah, a house will be built for him in Paradise: four before the Zuhr, two Rak’ah after Zuhr, two Rak’ah after Maghrib, two Rak’ah after the ‘Isha’ and two Rak’ah before Fajr.’”

SahihAl-Albani
SahihMuhammad Fouad Abd al-Baqi