Sunan an-Nasa'i, Book 12, Hadith 26 (In-Book) ⓘ
It was narrated that Qatadah said: "I heard Anas narrate that the Prophet said: "Bow and prostrate properly when you bow and prostrate.'"
أَخْبَرَنَا مُحَمَّدُ بْنُ عَبْدِ الأَعْلَى، قَالَ حَدَّثَنَا خَالِدٌ، قَالَ حَدَّثَنَا شُعْبَةُ، عَنْ قَتَادَةَ، قَالَ سَمِعْتُ أَنَسًا، يُحَدِّثُ عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ " أَتِمُّوا الرُّكُوعَ وَالسُّجُودَ إِذَا رَكَعْتُمْ وَسَجَدْتُمْ " .
also referenced under: Hadith 1054 (Reference) & Volume 2, Book 12, Hadith 1055 (DarusSalam)