Yuga-Vibhāga and Kāla-Pramāṇa
Measures of Time and the Four Yugas
एवं चतुर्युगे काल ऋतैः संध्यांशकैः स्मृतः / नियुतान्येव षडिंशान्निरसानि युगानि वै
evaṃ caturyuge kāla ṛtaiḥ saṃdhyāṃśakaiḥ smṛtaḥ / niyutānyeva ṣaḍiṃśānnirasāni yugāni vai
Thus the time of a Caturyuga is remembered together with the twilight periods (sandhyā) and their portions (sandhyāṃśa) of Kṛta and the other yugas; the measure of the yugas is sixteen niyutas, complete.