Sunan at-Tirmidhi (Jami-al-Tirmidhi), Chapter: Taharah (Purification)

said that Sayyidina Salman (RA) was told, "Indeed, your Prophet teaches you every thing, so much so thateven how to relieve yourself. Salman (RA) said. "Yes! He forbade us to face the qiblah when passing stool or urine, or to cleanse ourselves with the right hand, or to use dung or bones to cleanse. [A 23764, 23766, Muslim 262, Abu Dawud 7, Nisai 41,42, Ibn e Majah 316]