Perhaps you should try some spelling variations:
"analytical numerical theory" » "analysis numerical theory", "partial numerical theory", "analytical numerics theory", "analytical numerical theories", "analytical metrical theory"
"analytic number theory" » "analytic punumber theory"

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: (("analytical numerical theory") OR ("analytic number theory")).
• Removing quotes may allow a broader search: (( analytical numerical theory ) or ( analytic number theory )).
• Adding a wildcard symbol may retrieve word variants: (("analytical numerical theory") or ("analytic number theory"))*.