Perhaps you should try some spelling variations:
"multiple imputations research : july 2009" » "multiple imputation research : july 2009", "multiple implications research : july 2009", "multiple mutation research : july 2009", "multiple reputation research : july 2009", "multiple imputations research : july 2008", "multiple imputations research : july 2007", "multiple imputations research : july 2019"
"multi operations research : july 2009" » "mutation operations research : july 2009", "poultry operations research : july 2009", "runtime operations research : july 2009", "multi operations research : july 2008", "multi operations research : july 2007", "multi operations research : july 2019"

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

• Performing a fuzzy search may retrieve terms with similar spellings: (("multiple imputations research : july 2009") or ("multi operations research : july 2009"))~.
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• Adding a wildcard symbol may retrieve word variants: (("multiple imputations research : july 2009") or ("multi operations research : july 2009"))*.