Shiva Purana
तस्याभ्याशे तपस्तीव्रं लोकं स्रष्टुं समुत्सुकाः ॥ दिव्यं वर्षसहस्रं तु वायुभक्षास्समाचरन् ॥ ३४ ॥
They were eager to create the world by performing severe austerities in the practice of that. They lived for a thousand divine years eating the air.
english translation
tasyAbhyAze tapastIvraM lokaM sraSTuM samutsukAH ॥ divyaM varSasahasraM tu vAyubhakSAssamAcaran ॥ 34 ॥
hk transliteration by Sanscript