Thomson Reuters is the license holder for ISI indexing. They do so through Journal Citation Report. Though impact factor is not publicly available, their annual report list the recognised journals. So just going through the list and then google the relevant journal one might the original impact factor.
Journal Citation Reports
http://about.jcr.incites.thomsonreuters.com/
http://www.lib.uiowa.edu/hardin/impact-factors/
it shows how to locate official impact factor of journals. JCR is not publicly avaiallbe, you need to have web of science access that is thomson reuter.
http://thomsonreuters.com/en/products-services/scholarly-scientific-research/research-management-and-evaluation/journal-citation-reports.html
The recognized authority for evaluating journals
Description:
Journal Citation Reports® offers a systematic, objective means to critically evaluate the world's leading journals, with quantifiable, statistical information based on citation data. By compiling articles' cited references, JCR helps to measure research influence and impact at the journal and category levels, and shows the relationship between citing and cited journals. Available in Science and Social Sciences editions.
Impact Factor results are made available on a yearly basis (approximately June) following the year of coverage.
Researcgate some files uploaded
How can I find the list of Impact Factor 2015?
https://www.researchgate.net/post/How_can_I_find_the_list_of_Impact_Factor_20152
citefactor - it is not original impact factor but still may be useful.
http://www.citefactor.org/page/top-publications-engineering-computer-science
http://www.citefactor.org/search/keywords/journals/International+Journal+of+Industrial+and+Systems+Engineering
Journal Citation Reports
http://about.jcr.incites.thomsonreuters.com/
http://www.lib.uiowa.edu/hardin/impact-factors/
it shows how to locate official impact factor of journals. JCR is not publicly avaiallbe, you need to have web of science access that is thomson reuter.
http://thomsonreuters.com/en/products-services/scholarly-scientific-research/research-management-and-evaluation/journal-citation-reports.html
The recognized authority for evaluating journals
Description:
Journal Citation Reports® offers a systematic, objective means to critically evaluate the world's leading journals, with quantifiable, statistical information based on citation data. By compiling articles' cited references, JCR helps to measure research influence and impact at the journal and category levels, and shows the relationship between citing and cited journals. Available in Science and Social Sciences editions.
Impact Factor results are made available on a yearly basis (approximately June) following the year of coverage.
Researcgate some files uploaded
How can I find the list of Impact Factor 2015?
https://www.researchgate.net/post/How_can_I_find_the_list_of_Impact_Factor_20152
citefactor - it is not original impact factor but still may be useful.
http://www.citefactor.org/page/top-publications-engineering-computer-science
http://www.citefactor.org/search/keywords/journals/International+Journal+of+Industrial+and+Systems+Engineering