(70) باب صَوْمِ النَّبِيِّ صلى الله عليه وسلم - بِأَبِي هُوَ وَأُمِّي - وَذِكْرِ اخْتِلاَفِ النَّاقِلِينَ لِلْخَبَرِ فِي ذَلِكَ
It was narrate from Jubair bin Nufair that 'Aishah said:
"The Messenger of Allah used to be keen to fast on Mondays and Thursday."
Reference: Sunan an-Nasa'i 2360
In-book reference: Book 22, Hadith 271
English translation: Vol. 3, Book 22, Hadith 2362