Sahih Muslim
The Book of Fasting (Kitab Al-Sawm)
Book Number: 006 / Hadith Number: 2635
Abu Huraira (Allah be pleased with him) reported: We were talking about Lailat-ul-Qadr in the presence of the Messenger of Allah (may peace be upon him) and he said: He who amongst you remembers (the night) when the moon arose and it was like a piece of plate (at the fag end of the month in a state of waning).