Natyashastra
हंसपक्षकृतौ हस्तौ व्यावृतौ तालवृन्तवत् । उद्वृत्ताविति विज्ञेयावथवा तालवृन्तकौ ॥ १८६॥
The two Haṃsapakṣa hands are spread out, resembling a palm-leaf fan. These are known as Udvṛtta or alternatively as Tālavṛnta hands.
english translation
haMsapakSakRtau hastau vyAvRtau tAlavRntavat । udvRttAviti vijJeyAvathavA tAlavRntakau ॥ 186॥
hk transliteration by Sanscript