What has the author John F Genung written?

It seems you're asking about an author named John F. Genung. While there are people with that name, there's no widely recognized author with that name who has published significant works.

Perhaps you're thinking of a different name, or there's a typo in the name.

To help me find the right author, could you provide:

* Any other details you remember about the author: Do you know anything about their genre, era, or any specific books they might have written?

* Any other information about the books: Do you recall a title, a theme, or even a brief summary of the book?

With more information, I might be able to help you find the author you're looking for.