is this card authentic? i have heard that it is either supposed to have a blue or red back! http://cgi.ebay.com/1900s-Fan-Craze-Mordacai-Brown-Baseball-Card_W0QQitemZ8747659576QQcategoryZ86840QQssPageNa meZWDVWQQrdZ1QQcmdZViewItemthanks for the help!