Shiva Purana
अर्को ब्रह्मा तथा रुद्रो विष्णुश्चेति पुनः प्रिये ॥ ईशानादिषु संपूज्यास्तृतीयावरणे पुनः ॥ ३०॥
Again, dear one, the sun is Brahma, Rudra and Vishnu. They should be worshiped in the northeast and other places and again in the third covering.
english translation
arko brahmA tathA rudro viSNuzceti punaH priye ॥ IzAnAdiSu saMpUjyAstRtIyAvaraNe punaH ॥ 30॥
hk transliteration by Sanscript