Natyashastra
चतुष्कलो ह्यष्टकलः कलाः षोदश चैव हि । त्र्यस्रकालस्तु षड्भेदस्त्रिकलः षट्कलस्तथा ॥ २८॥
The Caturasra Tāla has four, eight, and sixteen Kalās. The Tryasra Tāla is of six kinds, with measures of three Kalās, six Kalās, and so on.
english translation
catuSkalo hyaSTakalaH kalAH Sodaza caiva hi । tryasrakAlastu SaDbhedastrikalaH SaTkalastathA ॥ 28॥
hk transliteration by Sanscript