Hadith 4:661
Ibn Idris narrated to us, from ‘Asim, from his father, from Khalid, who said: The Messenger of Allah (may Allah bless him and grant him peace) said: "I was shown the Night of Decree (Laylat al-Qadr), then I was made to forget it. So seek it in the last ten nights, in the odd-numbered ones."
حدثنا بن إدريس عن عاصم عن أبيه عن خالد قال قال رسول الله صلى الله عليه وسلم إني رأيت ليلة القدر فأنسيتها فاطلبوها في العشر الأواخر وترا