Shiva Purana
शिवभक्तो वसेन्नित्यं शिवलिंगं समाश्रितः । स्थाणुलिंगाश्रयेणैव स्थाणुर्भवति भूसुराः १५९ ।
The devotee of Śiva shall always resort to the phallic emblem of Śiva. O brahmins, one becomes Śiva by resorting to stationary phallic emblem.
english translation
zivabhakto vasennityaM zivaliMgaM samAzritaH । sthANuliMgAzrayeNaiva sthANurbhavati bhUsurAH 159 ।
hk transliteration by Sanscript