कृतं त्रेतायुगं चैव द्वापरं कलिरेव च । राज्ञो वृत्तानि सर्वाणि राजा हि युगमुच्यते ॥ ३०१ ॥
sanskrit
The various ways in which a king behaves (resemble) the Krita, Treta, Dvapara, and Kali ages; hence the king is identified with the ages (of the world).
english translation