Hadith
وَحَدَّثَنِي زِيَادٌ، عَنْ مَالِكٍ، عَنْ هِشَامِ بْنِ عُرْوَةَ، عَنْ أَبِيهِ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ " تَحَرَّوْا لَيْلَةَ الْقَدْرِ فِي الْعَشْرِ الأَوَاخِرِ مِنْ رَمَضَانَ " .
Ziyad related to me from Malik from Hisham ibn Urwa from his father that the Messenger of Allah, may Allah bless him and grant him peace, said, "Search for Laylat al-Qadr in the last ten days of Ramadan
Sahih · Salim al-Hilali
Muwatta Malik 698 ·Book 19, Hadith 9·Also available on sunnah.com·