(6) باب فِي الرَّجُلِ يَسْمَعُ السَّجْدَةَ وَهُوَ رَاكِبٌ وَفِي غَيْرِ الصَّلاَةِ
Narrated Abdullah ibn Umar:
The Messenger of Allah (ﷺ) used to recite the Qur'an to us. When he came upon the verse containing prostration, he would utter the takbir (Allah is most great) and we would prostrate ourselves along with him.The narrator 'Abd al-Razzaq said: Al-Thawri liked this tradition very much.Abu Dawud said: This was liked by him for this contains the uttering of takbir.
Reference: Sunan Abi Dawud 1413
In-book reference: Book 7, Hadith 13
English translation: Book 7, Hadith 1408