كتاب الْمَسَاجِدِ وَمَوَاضِعِ الصَّلاَةِ
5  
The Book of Mosques and Places of Prayer
(54)
Chapter: It is recommended to say qunut in all prayers if a calamity befalls the Muslims – and refuge is sought from Allah (regarding that). It is recommended to say qunut in Subh at all times. And the clarification that it is to be said after raising the head from bowing in the final rak`ah, and it is recommended to say it out loud
(54)
باب اسْتِحْبَابِ الْقُنُوتِ فِي جَمِيعِ الصَّلاَةِ إِذَا نزَلَتْ بِالْمُسْلِمِينَ نَازِلَةٌ ‏‏
Sahih Muslim 678 b

Al-Bari' reported that the Messenger of Allah (ﷺ) observed Qunut in the dawn and evening (prayers).

وَحَدَّثَنَا ابْنُ نُمَيْرٍ، حَدَّثَنَا أَبِي، حَدَّثَنَا سُفْيَانُ، عَنْ عَمْرِو بْنِ مُرَّةَ، عَنْ عَبْدِ الرَّحْمَنِ بْنِ أَبِي لَيْلَى، عَنِ الْبَرَاءِ، قَالَ قَنَتَ رَسُولُ اللَّهِ صلى الله عليه وسلم فِي الْفَجْرِ وَالْمَغْرِبِ ‏.‏
Reference : Sahih Muslim 678b
In-book reference : Book 5, Hadith 389
USC-MSA web (English) reference : Book 4, Hadith 1444
  (deprecated numbering scheme)