Bukhari :: Book 3 :: Volume 31 :: Hadith 202

Narrated Abu Huraira:

My friend (the Prophet ) advised me to observe three things:

(1) to fast three days a month;

(2) to pray two Rakat of Duha prayer (fore-noon prayer); and

(3) to pray Witr before sleeping.

Source materials are from the University of Southern California MSA site
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