From the Mezzanine docs:
By default the template pages/page.html is used, but if a custom template exists it will be used instead. The check for a custom template will first check for a template with the same name as the Page instance’s slug, and if not then a template with a name derived from the subclass model’s name is checked for. So given the above example the templates pages/dr-seuss.html and pages/author.html would be checked for respectively.
The question is where does Mezzanine CMS gets the slug for an instance of a page? Is it from the title attribute?