Shiva Purana

siva.sh/siva-purana/vishweshwara-samhita/18/72

हृदयं चाग्निसारेण त्वपां सारेण वैकटिम् । जानु चावनिसारेण तद्वत्सर्वं तदंगकम् ७२ ।

sanskrit

The essence of the Fire principle constitutes His heart, that of the principles of waters the hip and that of the principle of the Earth the knees. Thus the other limbs too.

english translation

hRdayaM cAgnisAreNa tvapAM sAreNa vaikaTim | jAnu cAvanisAreNa tadvatsarvaM tadaMgakam 72 |

hk transliteration by Sanscript