Natyashastra
सर्वैश्चाषगतैः पादैः परिभ्राम्य तु मण्डलम् । एतच्चाषगतं विद्यान्नियुद्धे चापि मण्डलम् ॥ ६७॥
By moving in a circle with all the feet in the manner of a bird, this formation is recognized as the "Chāṣagata" formation, which is also used in combat.
english translation
sarvaizcASagataiH pAdaiH paribhrAmya tu maNDalam । etaccASagataM vidyAnniyuddhe cApi maNDalam ॥ 67॥
hk transliteration by Sanscript