Natyashastra
वामः समुन्नतकटिश्चायते स्थानके भवेत् । आवाहने विसर्गे च तथा निर्वर्णनेषु च ॥ १६४॥
In the Āyata posture, the left waist is slightly raised. This posture is to be used in invocation, dismissal, and description (or expression).
english translation
vAmaH samunnatakaTizcAyate sthAnake bhavet । AvAhane visarge ca tathA nirvarNaneSu ca ॥ 164॥
hk transliteration by Sanscript