Mishkat al-Masabih #322

Abu Huraira reported God’s messenger as saying, "I am to you just like a father to his son, for I give you instruction. When you go to relieve yourselves do not face or turn your back to the qibla.” He commanded that three stones be used, he forbade the use of dung and decayed bones, and he forbade that a man should cleanse himself with his right hand. Ibn Majah and Darimi transmitted it.