Natyashastra
प्रत्येकं पातनान्येषु दल्लाः सप्त भवन्ति हि । शम्यातालकृतानीह सन्निपातकृतानि च ॥ १७७॥
In each of these sections, there are seven groups formed by Śamyā, Tāla, and Sannipāta.
english translation
pratyekaM pAtanAnyeSu dallAH sapta bhavanti hi । zamyAtAlakRtAnIha sannipAtakRtAni ca ॥ 177॥
hk transliteration by Sanscript