Perhaps you should try some spelling variations:
"modified notion approximation algorithms" » "modified network approximation algorithms", "modified time approximation algorithms", "modified one approximation algorithms"
"modified study evaluation algorithm" » "modified study evolution algorithm", "modified study estimation algorithm", "modified study solution algorithm", "modified load evaluation algorithm", "modified time evaluation algorithm"

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 notion approximation algorithms") OR ("modified study evaluation algorithm"))~.
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