Manusmriti

siva.sh/manusmriti/2/63

उद्धृते दक्षिणे पाणावुपवीत्यौच्यते द्विजः । सव्ये प्राचीनावीती निवीती कण्ठसज्जने ॥ ६३ ॥

sanskrit

A twice-born man is called upavitin when his right arm is raised (and the sacrificial string or the dress, passed under it, rests on the left shoulder); (when his) left (arm) is raised (and the string, or the dress, passed under it, rests on the right shoulder, he is called) prakinavitin; and nivitin when it hangs down (straight) from the neck.

english translation

uddhRte dakSiNe pANAvupavItyaucyate dvijaH | savye prAcInAvItI nivItI kaNThasajjane || 63 ||

hk transliteration by Sanscript