Shiva Purana
अनलाचलसंकाशं यदिदं लिंगमुत्थितम् । अरुणाचलमित्येव तदिदं ख्यातिमेष्यति २१ ।
Since the phallic emblem rose high resembling a mountain of fire, this shall be famous as Ruddy (Aruṇa) mountain.
english translation
analAcalasaMkAzaM yadidaM liMgamutthitam । aruNAcalamityeva tadidaM khyAtimeSyati 21 ।
hk transliteration by Sanscript