Natyashastra
ततश्च तालः कर्तव्या शम्या चैव तु पञ्चमी । प्रवेशो ?? षष्ठः कर्तव्यस्तर्जनीकृतः ॥ ४२॥
Then the Tāla is to be shown, followed by the fifth, which is the Śamyā. The sixth is the Praveśa, to be performed with the thumb, and it is to be shown using the index finger.
english translation
tatazca tAlaH kartavyA zamyA caiva tu paJcamI । pravezo ?? SaSThaH kartavyastarjanIkRtaH ॥ 42॥
hk transliteration by Sanscript