The Book of Prayers (Kitab Al-Salat)
Muslim :: Book 4 : Hadith 920
Qutba b. Malik reported: I said prayer and the Messenger of Allah (may peace be upon him) led it and he recited" Qaf. (I.). By the Glorious Qur'an," till he recited" and the tall palm trees" (l. 10). I wanted to repeat it but I could not follow its significance.