Shiva Purana
कपालं ब्राह्मणः सद्यो भैरवस्य करांबुजात् ॥ पपात भुवि तत्तीर्थमभूत्कापालमोचनम् ॥ ५६ ॥
The skull of Brahmā fell on the ground suddenly from the lotus-like hand of Bhairava. The holy centre then became Kapālamocana.
english translation
kapAlaM brAhmaNaH sadyo bhairavasya karAMbujAt ॥ papAta bhuvi tattIrthamabhUtkApAlamocanam ॥ 56 ॥
hk transliteration by Sanscript