He is also considered an authority on the Pakistan independence movement.

He was considered an authority on the subject of golf.

He is considered an authority in matters of a liberal arts education.

He is considered an authority on the history of Kerala.

Although relatively young, he was nonetheless considered an authority on technical education.

I was already considered an authority on physical training in Norway.

For half a century it was considered a leading authority on exchange rates.

He is considered an authority on issues of immigration, and the Arab world.

Why should anyone be considered an authority on anything outside of their area of study?

He is considered an authority on the history and theory of free banking.