Shiva Purana
परमात्मानमपि च प्रणवाद्यं नमोंतकम् ॥ चतुर्थ्यन्तं जपित्वाऽथ सक्तुमुष्टिं प्रगृह्य च ॥ ९४ ॥
I also offer my obeisances to the Supreme Soul who plays the oṁkāra. After chanting the fourth mantra he took hold of his fist.
english translation
paramAtmAnamapi ca praNavAdyaM namoMtakam ॥ caturthyantaM japitvA'tha saktumuSTiM pragRhya ca ॥ 94 ॥
hk transliteration by Sanscript