Arthashastra
चातुर्मास्येष्व् अर्ध मासिकम् अघातम्, पौर्णमासीषु च चातूरात्रिकं राज देश नक्षत्रेष्व् ऐकरात्रिकम् ॥
He should prohibit the slaughter of animals for half a month during the period of Cháturmásya (from July to September), for four nights during the full moon, and for a night on the day of the birth-star of the conqueror or of the national star.
english translation
cAturmAsyeSv ardha mAsikam aghAtam, paurNamAsISu ca cAtUrAtrikaM rAja deza nakSatreSv aikarAtrikam ॥
hk transliteration by Sanscript