The Book of Fasting (Kitab Al-Sawm)

Muslim :: Book 6 : Hadith 2620

Salim b. 'Abdullah b. 'Umar reported that his father said: I heard Allah's Messenger (may peace be upon him) as saying: So far as Lailat-ul-Qadr is concerned. some persons among you have seen it (in a dream) in the first week and some persons among you have been shown that it is in the last week; so seek it in the last ten (nights).

Source materials are from the University of Southern California MSA site
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