Shiva Purana

siva.sh/siva-purana/saturda-samhita/9/56

कपालं ब्राह्मणः सद्यो भैरवस्य करांबुजात् ।। पपात भुवि तत्तीर्थमभूत्कापालमोचनम् ।। ५६ ।।

sanskrit

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