Here is an article I thought you might enjoy. It is posted on the Mystery Fanfare blogsite of Janet Rudolph. I get her newsletter and really enjoy the articles that she posts.

This one was written by Cleo Coyle and there is more information about the couple behind that pseudonym as well.

Here is a link to Janet's blog/Cleo's article:

Sightseeing is Murder: A Killer New York Tour by Cleo Coyle