Ramayana
पूर्णे वर्षसहस्रान्ते तं तं विधिमकल्पयत् । जलाशी मारुताहारो निराहारस्तथैव च ॥ 7-3-12 ॥
At the completion of each thousand years he undertook this observance and that: subsisting on water, feeding on the wind, and likewise taking no food at all.
english translation