Kautilya's Arthashastra 2.6.12

2.6.12

rājavarṣaṃ māsaḥ pakṣo divasaś ca vyuṣṭam, varṣāhemantagrīṣmāṇāṃ tṛtīyasaptamā divasonāḥ pakṣāḥ śeṣāḥ pūrṇāḥ, pṛthagadhimāsakaḥ, iti kālaḥ //

The royal year, the month, the paksha, the day, the dawn (vyushta), the third and seventh pakshas of (the seasons such as) the rainy season, the winter season, and the summer short of their days, the rest complete, and a separate intercalary month are (the divisions of time).