Sunan Ibn Majah
310
Sahih+3

Abdullah bin Abu Qatadah said:"My father told me that he heard the Messenger of Allah say: 'When anyone of you urinates, let him not touch his penis with his right hand nor clean himself with his right hand.'" Another chain with similar wording

SahihAl-Albani
SahihMuhammad Fouad Abd al-Baqi