Perhaps you should try some spelling variations:
"modified coverage approximation algorithms" » "modified average approximation algorithms"
"modified adam classification algorithm" » "modified a classification algorithm", "modified gas classification algorithm", "modified image classification algorithm", "modified df classification algorithm", "modified near classification 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 coverage approximation algorithms") OR ("modified adam classification algorithm"))~.
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