Perhaps you should try some spelling variations:
options research » actions research, optics research, operations research
option research » opinion research, action research, optics research
multi option » multi location, multi population, multi ratios
mali options » scale options, i options, iii options
july 2009 » july 2008, july 2007, 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: (( multi option research : july 2009 ) OR ( mali options research : july 2009 ))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(( multi option research : july 2009 ) OR ( mali options research : july 2009 ))".
• Adding a wildcard symbol may retrieve word variants: (( multi option research : july 2009 ) OR ( mali options research : july 2009 ))*.