Debi, I don't know what "SEO" means (Search Engine Optimization?), but there is a problem with any site if a link is broken. There are stable urls, but they are difficult to come across. Most people would probably click on a reference that shows that is came from FamilySearch, as long as they can see the url, but we all know that websites are spoofed all the time. Personally, I prefer to see the information about the source, as well as the url. That way I can choose whether to click or not.