Natyashastra
अध्यर्द्वाद्धि तृतीयाच्च सन्निपाताः प्रमाणतः । उल्लोप्यके विदारी तु स्मृता वैहायसे तथा ॥ १८७॥
But in case of the Ullopyaka and the Vaihāyasa ॥ the number of॥ Vidārīs will be half as much more in the third Sannipāta.
english translation
adhyardvAddhi tRtIyAcca sannipAtAH pramANataH । ullopyake vidArI tu smRtA vaihAyase tathA ॥ 187॥
hk transliteration by Sanscript