Perhaps you should try some spelling variations:
"modified coverage approximation algorithms" » "modified average approximation algorithms"
"modified response estimation algorithms" » "modified response estimation algorithm", "modified response optimization algorithms", "modified response optimisation algorithm", "modified pose estimation algorithms", "modified response association 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 response estimation algorithms") OR ("modified coverage approximation algorithms"))~.
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