The works of Ādi Śaṅkarācārya

Viṣṇusahasranāmastotram

Verse 349

दिमारम्भं करोति इति वा ॥इति नाम्नां तृतीयं शतं विवृतम् ॥

In plain words

Or take it this way: he makes the beginning, the very setting-out. That is the second reading. And with that, the third hundred of the names has been opened out.

Close to the Sanskrit

Or: he makes the beginning, the commencement — thus. Thus the third hundred of the names has been explained.