What has the author John Penn written?

There are several people named John Penn, so it's important to specify which one you are interested in. Could you please provide more context?

For example:

* Which field is John Penn in? Is he a novelist, historian, scientist, etc.?

* What is his nationality? This will help narrow down the search.

* Do you have any other information about him?

With more information, I can help you find the books written by the specific John Penn you're looking for.