Matsya Purana 167.30

167.30

evaṃ varṣaśataṃ sāgraṃ mārkaṇḍeyasya dhīmataḥ
carataḥ pṛthivīṃ sarvāṃ na kukṣyantaḥ samīkṣitaḥ //

He also saw many people performing various sacrifices and hundreds of Brâhmaṇas The Brâhmaṇas were all pursuing the highest path of duty and he also found the four orders well established In that way, the great sage Mârkandeya passed a divine century within Viṣṇu But he could not find the end of the belly of Nârâyana—28 30