Shiva Purana
एतदेव पदं प्राप्यं यतीनां भवितात्मनाम् ॥ सदाशिवोपासकानां प्रणवासक्तचेतसाम् ॥ ३२ ॥
This region is attainable by the pious ascetics who worship Sadāśiva, with the minds fixed on the Praṇava.
english translation
etadeva padaM prApyaM yatInAM bhavitAtmanAm ॥ sadAzivopAsakAnAM praNavAsaktacetasAm ॥ 32 ॥
hk transliteration by Sanscript