Shiva Purana
साक्षाद्रुद्रावतारोऽसौ दधीच वरतेजसः॥ प्रादुर्भूतस्स्वयन्तात स्वलीलाकरणे क्षमः॥ ४७।
O dear, it was the incarnation of Rudra himself born of the sage Dadhīci. He was competent to perform his divine sports. He therefore manifested himself.
english translation
sAkSAdrudrAvatAro'sau dadhIca varatejasaH॥ prAdurbhUtassvayantAta svalIlAkaraNe kSamaH॥ 47।
hk transliteration by Sanscript