What has the author Erich Knopf written?

There is no known author named "Erich Knopf". It's possible there's a typo in the name, or the author may not be well-known.

To help me find the correct author, could you please provide:

* Any other information about the author or their work: Do you know anything about the type of books they write, the genre, or any specific titles?

* Any alternative spellings of the name: Are you sure about the spelling?

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