What has the author Herbert Mueller written?

There is no widely known or established author named "Herbert Mueller". It's possible that:

* The name is misspelled. Double check the spelling and try searching again.

* The author is less known. It might be a regional or niche author. Try looking for specific books or genres that they might write in.

* The author is using a pen name. Try searching for different variations of the name or any other known aliases.

To help me narrow down the search, could you please provide any additional information about Herbert Mueller, such as:

* Genre of writing: What kind of books do they write?

* Any specific titles: Do you know any books they've written?

* Time period: When were the books published?

* Any other clues: Are there any specific details you know about them?

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