Natyashastra
देहः स्वाभाविको यत्र भवेत्समनखं तु तत् । पताकाञ्जलि वक्षःस्थं प्रसारितशिरोधरम् ॥ ६६॥
When the body is natural, with the nails aligned, the hands in the flag gesture, the chest expanded, and the head stretched forward.
english translation
dehaH svAbhAviko yatra bhavetsamanakhaM tu tat । patAkAJjali vakSaHsthaM prasAritazirodharam ॥ 66॥
hk transliteration by Sanscript