Prayer (Kitab Al-Salat)
2/165. Chapter:
The Manner Of Prostration
Sunan Abi Dawud
حَدَّثَنَا مُسْلِمُ بْنُ إِبْرَاهِيمَ، حَدَّثَنَا شُعْبَةُ، عَنْ قَتَادَةَ، عَنْ أَنَسٍ، أَنَّ النَّبِيَّ صلى الله عليه وسلم قَالَ " اعْتَدِلُوا فِي السُّجُودِ وَلاَ يَفْتَرِشْ أَحَدُكُمْ ذِرَاعَيْهِ افْتِرَاشَ الْكَلْبِ " .
Anas reported the Messenger of Allah(ﷺ) as saying; Adopt a moderate position when prostrating yourselves, and see that none of you stretches out his forearms(on the ground) like a dog.
Reference : Sunan Abi Dawud 897In-book reference : Book 2, Hadith 507English translation : Book 2, Hadith 896