Perhaps you should try some spelling variations:
"modified network approximation algorithm" » "certified network approximation algorithm", "defined network approximation algorithm", "modified near approximation algorithm"
"modified average approximation algorithms" » "modified coverage approximation algorithms"

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: (("modified average approximation algorithms") OR ("modified network approximation algorithm"))~.
• Removing quotes may allow a broader search: (( modified average approximation algorithms ) or ( modified network approximation algorithm ))~.
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