وَحَدَّثَنِي حَرْمَلَةُ بْنُ يَحْيَى، أَخْبَرَنَا ابْنُ وَهْبٍ، أَخْبَرَنِي يُونُسُ، عَنِ ابْنِ شِهَابٍ، أَخْبَرَنِي سَالِمُ بْنُ عَبْدِ اللَّهِ بْنِ عُمَرَ، أَنَّ أَبَاهُ، - رضى الله عنه - قَالَ سَمِعْتُ رَسُولَ اللَّهِ صلى الله عليه وسلم يَقُولُ لِلَيْلَةِ الْقَدْرِ ‏"‏ إِنَّ نَاسًا مِنْكُمْ قَدْ أُرُوا أَنَّهَا فِي السَّبْعِ الأُوَلِ وَأُرِيَ نَاسٌ مِنْكُمْ أَنَّهَا فِي السَّبْعِ الْغَوَابِرِ فَالْتَمِسُوهَا فِي الْعَشْرِ الْغَوَابِرِ ‏"‏ ‏.‏

Salim b. 'Abdullah b. 'Umar reported that his father said: I heard Allah's Messenger (PBUH) 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). Translation Not Available

Book Ref: Sahih Muslim Book 13 Hadith 2620
Web Ref:  Sahih Muslim Book 6 Hadith 1165 d