Abu Qatada reported God’s messenger as saying, "When one of you drinks he must not breathe into the vessel, and when he goes to relieve himself he must not touch his penis with his right hand, or wipe himself with his right hand.” (Bukhari and Muslim.)
Hadith Referenceمشكوة المصابيح / كتاب الطهارة / 340
Hadith Gradingالألبانی:مُتَّفَقٌ عَلَيْهِ | زبیر علی زئی:متفق عليه
Hadith Takhrij´تحقيق و تخريج: محدث العصر حافظ زبير على زئي رحمه الله` «متفق عليه، رواه البخاري (153) و مسلم (63/ 267)»