Go to the Journal Citation Reports and find a ranked list of top journals in
Operations Research/Management Sciences
You may need to browse journals in other engineering categories and other disciplines to find all journals of interest.
Definition: A measure of the frequency with which the "average article" in a journal has been cited in a particular year or period. Thomson Reuters
Calculation: 2012 impact factor = A/B.
Available from: Journal Citation Reports/JCR
What should concern you about cited reference searching and impact factors?
Gaming the System