(81) باب صَوْمِ ثَلاَثَةِ أَيَّامٍ مِنَ الشَّهْرِ
Abu Hurairah said:
"The Messenger of Allah commanded me to pray two Rakahs of Duah,nt to sleep until after praying Witr and to fast three days of each month. (Sahih). (DE)
Reference (DE): Sunan an-Nasa'i 2406 (DE)
In-book reference (DE): Book 22, Hadith 317 (DE)
English translation (DE): Vol. 3, Book 22, Hadith 2408 (DE)