Shiva Purana
तपः कर्तुं समारेभे यत्र ते सहचारिणः॥ स वै तत्र निराहारो वायुभक्षो महातपाः ॥ ५॥
Without taking in any food, breathing in only air he began to perform a great penance in the spot where those comrades were present.
english translation
tapaH kartuM samArebhe yatra te sahacAriNaH॥ sa vai tatra nirAhAro vAyubhakSo mahAtapAH ॥ 5॥
hk transliteration by Sanscript