مُوَطَّأُ مَالِكٍ
Muwatta Malik 701
I'tikaf in Ramadan
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, (ﷺ), said, "Search for Laylat al-Qadr in the last ten days of Ramadan."
Arabic/English book reference: Book 19, Hadith 11