Shiva Purana
स्नापयेद्देवदेवेशं प्रणवेन शिवेन च ॥ विशेषार्घ्योदकेनापि प्रणवेनाभिषेचयेत् ॥ ३९॥
One should bathe Lord of the gods and goddesses with the oṁkāra and Lord Śiva. One should also consecrate the body with special arghya water and the oṁkāra.
english translation
snApayeddevadevezaM praNavena zivena ca ॥ vizeSArghyodakenApi praNavenAbhiSecayet ॥ 39॥
hk transliteration by Sanscript