Natyashastra
चतुष्कलाऽन्त्यया तुल्या षष्ठी मद्रकमात्रया । इति पादस्तथाष्टौ च कलापादादुपोहनम् ॥ २९३॥
The last (fourth) Kalā is equal to the sixth Mātrā of the Madraka. Thus, for the Pāda, there should be eight Kalās in the Upohana of the Kalā-pāda.
english translation
catuSkalA'ntyayA tulyA SaSThI madrakamAtrayA । iti pAdastathASTau ca kalApAdAdupohanam ॥ 293॥
hk transliteration by Sanscript