Perhaps you should try some spelling variations:
"modified one approximation algorithms" » "modified time approximation algorithms", "modified _ approximation algorithms", "modified rough approximations algorithms", "modified male approximation algorithms", "modified near approximation algorithms", "modified orca approximation algorithms"
"machinery using methods algorithm" » "machines using methods algorithm", "machinery nursing methods algorithm", "machinery making methods algorithm", "machinery counting methods algorithm"

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("modified one approximation algorithms") or ("machinery using methods algorithm"))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (("modified one approximation algorithms") OR ("machinery using methods algorithm")).
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