Perhaps you should try some spelling variations:
"multiple options research : july 2009" » "multiple imputations research : july 2009", "multi option research : july 2009", "multiple operations research : july 2009", "multiple action research : july 2009", "multiple opinion research : july 2009", "multiple options research : july 2006", "multiple options research : july 2013", "multiple options research : july 2011"
"multiple options research : july 2012" » "multiple imputations research : july 2012", "multi option research : july 2012", "multiple operations research : july 2012", "multiple action research : july 2012", "multiple opinion research : july 2012", "multiple options research : july 2013"

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