Shiva Purana
स्वतंत्रो दशधा पूर्वं तथाष्टादशधा पुनः ॥ कामिकादिसमाख्याभिस्सिद्धः सिद्धान्तसंज्ञितः ॥ १२ ॥
The independent texts were originally ten but supplemented subsequently by eight more so as to constitute eighteen texts. They are called Kāmika etc., and the entire literature is called “Śaiva Siddhānta”
english translation
svataMtro dazadhA pUrvaM tathASTAdazadhA punaH ॥ kAmikAdisamAkhyAbhissiddhaH siddhAntasaMjJitaH ॥ 12 ॥
hk transliteration by Sanscript