What has the author Walter Lehn written?

It seems you're asking about an author named "Walter Lehn." However, there is no widely known author with that name. It's possible that:

* There's a misspelling: Perhaps you're thinking of a different author with a similar name. Could you double-check the spelling?

* The author is less known: It's possible that Walter Lehn is a lesser-known author. If you have any more information about their work (like a genre or specific book titles), it might help in finding more details.

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