Natyashastra
उरू च वलितौ यस्मिन्वलितोरुकमुच्यते । आवर्त्य शुकतुण्डाख्यमूरुपृष्ठे निपातयेत् ॥ ६४॥
When the thighs are in a circular movement, it is known as the Valitoru, and the hands are placed on the thigh in the Śukatuṇḍa gesture, performing a circular motion.
english translation
urU ca valitau yasminvalitorukamucyate । Avartya zukatuNDAkhyamUrupRSThe nipAtayet ॥ 64॥
hk transliteration by Sanscript