Arthashastra
उपरुद्ध परिक्षिप्तयोर् उपरुद्धम् अन्यतो निष्क्रम्य उपरोद्धारं प्रतियुध्येत, न परिक्षिप्तं सर्वतः प्रतिरुद्धम् ॥
Of obstructed and surrounded armies, that which is prevented from its movements in one direction may be taken to fight against the obstructor in another direction, but not the army whose movements are obstructed on all sides.
english translation
uparuddha parikSiptayor uparuddham anyato niSkramya uparoddhAraM pratiyudhyeta, na parikSiptaM sarvataH pratiruddham ॥
hk transliteration by Sanscript