* The name is misspelled: Perhaps you're thinking of a different author with a slightly different name.
* The author is relatively unknown: There could be an author with this name who has published works in a niche area or who is relatively new to the writing world.
* The author goes by a pseudonym: It's possible that George L. Tappan is a pen name.
Could you please provide more information about the author or their work? This will help me find more accurate information about them.