Perhaps you should try some spelling variations:
"statt revolution sources" » "statt resolution source", "statt evolution resources", "statt evolutionary sources", "statt evolution sources", "states revolution sources", "state evolution sources"
"statt revolution series" » "statt revolution serielles", "statt revolution studies", "statt revolution unseres", "statt evolution series", "states revolution series", "state evolution series"

Try widening your search to All Fields.

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: (("statt revolution series") OR ("statt revolution sources")).
• Removing quotes may allow a broader search: (( statt revolution series ) or ( statt revolution sources )).
• Adding a wildcard symbol may retrieve word variants: (("statt revolution series") or ("statt revolution sources"))*.