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

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