Shiva Purana
अजेयश्चामरश्चैव सोऽद्यापि तपसांनिधिः ॥ लिंगार्चनरतो नित्यं दृश्यते सिद्धचारणैः ॥ ५८ ॥
Even today Siddhas and Cāraṇas sec this storehouse of penance deathless and invincible engaged in worshipping the phallic image.
english translation
ajeyazcAmarazcaiva so'dyApi tapasAMnidhiH ॥ liMgArcanarato nityaM dRzyate siddhacAraNaiH ॥ 58 ॥
hk transliteration by Sanscript