(5) باب مَا جَاءَ فِي الْوِتْرِ بِسَبْعٍ
Umm Salamah narrated:
"The Prophet would perform Witr with thirteen [Rak'ah]. When he was older and became weak he performed Witr with seven." (TH)
Reference (TH): Jami` at-Tirmidhi 457, 458 (TH)
In-book reference (TH): Book 3, Hadith 6 (TH)
English translation (TH): Vol. 1, Book 3, Hadith 457 (TH)