Perhaps you should try some spelling variations:
"defined network approximation algorithm" » "defined network approximation algorithms"
"modified network estimation algorithms" » "modified network estimation algorithm", "modified network optimization algorithms", "modified network optimisation algorithm", "certified network estimation algorithms", "modified near estimation algorithms"

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (("modified network estimation algorithms") or ("defined network approximation algorithm"))~.
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