I'm sorry, but I couldn't find any information about an author named David Gillis. It's possible that there may not be a well-known author by that name, or the information may not be readily available. If you have any additional details or context about the author, I may be able to help you further. Alternatively, if you meant to ask about a different author or have a different question, please feel free to let me know so I can assist you better.
