Natyashastra
द्विविधं मद्रकं तत्र चतुर्वस्तु त्रिवस्तु च । शीर्षकेण समायुक्तं तच्च ज्ञेयं त्रिवस्तुकम् ॥ १९०॥
There are two kinds of Madraka there, and it contains four Vastus and three Vastus; combined with the Śīrṣaka, it is to be understood as the three-Vastu section.
english translation
dvividhaM madrakaM tatra caturvastu trivastu ca । zIrSakeNa samAyuktaM tacca jJeyaM trivastukam ॥ 190॥
hk transliteration by Sanscript