Shiva Purana
उपमन्युरुवाच ॥ अथाविरभवत्तत्र सनादं शब्दलक्षणम् ॥ ओमित्येकाक्षरं ब्रह्म ब्रह्मणः प्रतिपादकम् ॥ १ ॥
Upamanyu said:— Then there manifested the single-syllabled Brahman in the characteristic way o ॥ ?॥ a word with its sound ‘Om’. It expressed the Brahman.
english translation
upamanyuruvAca ॥ athAvirabhavattatra sanAdaM zabdalakSaNam ॥ omityekAkSaraM brahma brahmaNaH pratipAdakam ॥ 1 ॥
hk transliteration by Sanscript