They would not (I hope) reveal their sources in court.

But then she would reveal her discomfort and its only possible source.

I need not reveal my knowledge or its source to you!

The Post will not reveal the source of the letters, a spokesman said.

The main problem, of course, would be not to reveal the source.

Except to say that it comes from outside the country, I cannot reveal my source, even to you.

He got maybe twenty yards before the bend in the road revealed the source of the light.

You may act upon anything you learn here, but not reveal the source of your knowledge.

Arrests are often because they refuse to reveal their sources in court.

Journalists can also be forced to reveal sources on grounds of national security.