Shiva Purana
ब्रह्माणं सचतुर्थ्यन्तं स्वाहांतान्प्रणवा दिकान् ॥ संजप्य वाचयित्वाऽथ पुण्याहं च ततः परम् ॥ १६ ॥
Brahma with the fourth end of the Svaha ends with the oṁkāra and the directions. After chanting the mantra and reciting the holy mantra thereafter.
english translation
brahmANaM sacaturthyantaM svAhAMtAnpraNavA dikAn ॥ saMjapya vAcayitvA'tha puNyAhaM ca tataH param ॥ 16 ॥
hk transliteration by Sanscript