Sahih Muslim Book 4, Hadith Number 998.

Chapter : How the limbs should work in prostration and forbiddance to fold clothing and hair and plaiting of hair in the prayer.

This Hadith has been narrated by Shu’ba with the same chain of transmitters. And in the Hadith transmitted by Ibn Ja’far (the words are): “None of you should stretch out his forearms like the stretching out of a dog.”