Sunan an-Nasa'i, Hadith 824 ⓘ
It was narrated from Anas that the Prophet used to make his prayer very brief but still complete when leading people.
أَخْبَرَنَا قُتَيْبَةُ، قَالَ حَدَّثَنَا أَبُو عَوَانَةَ، عَنْ قَتَادَةَ، عَنْ أَنَسٍ، أَنَّ النَّبِيَّ صلى الله عليه وسلم كَانَ أَخَفَّ النَّاسِ صَلاَةً فِي تَمَامٍ .
also referenced under: Book 10, Hadith 48 (In-Book) & Volume 1, Book 10, Hadith 825 (DarusSalam)