Shiva Purana
शतकोटिप्रमाणेन विस्तीर्णं ग्रंथसंख्यया ॥ कथितं परमेशेन तत्र पूजा कथं प्रभोः ॥ ४ ॥
It is about one hundred crore times as vast as the number of books. The Supreme Lord described how to worship the Lord there.
english translation
zatakoTipramANena vistIrNaM graMthasaMkhyayA ॥ kathitaM paramezena tatra pUjA kathaM prabhoH ॥ 4 ॥
hk transliteration by Sanscript