Shiva Purana
नन्दीश्वर उवाच ॥ एतान्वरान्प्रगृह्याथ तत्क्षणात्कालभैरवः ॥ वामांगुलिनखाग्रेण चकर्त च विधेश्शिरः ॥ ५२॥
Nandīśvara said:— After receiving all these boons. Kāla-Bhairava, in a trice, cut off Brahmā’s head with the tip of the nails of the fingers of his left hand.
english translation
nandIzvara uvAca ॥ etAnvarAnpragRhyAtha tatkSaNAtkAlabhairavaH ॥ vAmAMgulinakhAgreNa cakarta ca vidhezziraH ॥ 52॥
hk transliteration by Sanscript