def titlepage(wobj)
      s = @epub.titlepage
      if !s.nil? && !wobj.nil?
        wobj.puts s
      end
    end
def titlepage(wobj)
      s = @epub.titlepage
      if !s.nil? && !wobj.nil?
        wobj.puts s
      end
    end
Write title file (copying) to IO object +wobj+.