Sahih Muslim Book 4, Hadith Number 1016.

Chapter : The excellence of the prayer and the way it is begun and the excellence of Ruku’ and moderation in it and prostration and moderation in it, etc.

‘Aun b. Abu Juhaifa narrated from the Apostle of Allah (may peace be upon him) on the authority of his father a Hadith like that of Sufyan, and ‘Umar b. Abu Za’ida made this addition: Some of them tried to excel the others (in obtaining water), and in the Hadith transmitted by Malik b. Mighwal (the words are): When it was noon, Bilal came out and summoned (people) to (noon) prayer.