Natyashastra
वाद्यं गतिप्रचारश्च ध्रुवा तालस्तथैव च । संक्षिप्तान्येव कार्याणि त्र्यश्रे नृत्तप्रवेदिभिः ॥ १४२॥
By those well-versed in the art of dance, the triangular form should be executed with concise elements: the musical accompaniment, the movement of the feet, the dhruva (a specific type of song), and the tāla (a rhythmic cycle).
english translation
vAdyaM gatipracArazca dhruvA tAlastathaiva ca । saMkSiptAnyeva kAryANi tryazre nRttapravedibhiH ॥ 142॥
hk transliteration by Sanscript