A couple of years ago, I inherited my aunt's entire collection of presidential and political memorabilitia. Included with the lot is a book signed by JFK, with a personal message to our town's mayor at the time. I am considering selling the book and would like to get the signature authenticated. Can someone recommend an authenticator or service that is reputable? I've done some research and have ended up more confused than when I started. Any input and direction is appreciated! Thank you!