Mīmāṃsā and Vedanta consider vedas too be eternal and authoress. But if a book exists it must have an author. And what is the source of vedas according to these schools. They don't even believe vedas are authored by the God. Source

The author of the Vedas should either be God or humans.

My questions : How can vedas be authorless?

And what is the source(if they are authorless) of the Vedas according to these schools?

Mīmāṃsā and Vedanta consider vedas to be eternal and authoress. But if a book exists it must have an author. And what is the source of vedas according to these schools. They don't even believe vedas are authored by the God. Source

The author of the Vedas should either be God or humans.

My questions : How can vedas be authorless?

And what is the source  (if they are authorless) of the Vedas according to these schools?