Does anybody know how to find how often a specific researcher is cited?
A library (at least a college library) should have a collection called the citation index. Sometime, you can even access several citation database online (at least for the sciences). Since you did not indicate where you are, and what kind of facilities you have access to, there is no way I can give a specific answer to this. So just go to a library, and ask the librarian if he or she can help you with what you are trying to find.
I'm in Heidelberg, Germany. I checked in the library. Do you know who publishes such information and how often? They don't have it. Do you know where can I find this information online? I'm interested specifically in physics citations and life sciences.
You can check how many citations a specific paper received on webofscience.
Some publishers will provide links to other sources citing an article when you access the article online, but that will just tell you an answer for a single publication.
Science Citation Index is another resource, which ZapperZ mentioned, and the primary one to use for such a purpose. I think they have an online resource now, but you'll just have to do a web search that to find out. If they don't have an online resource, it's going to take a lot of work to find out a lifetime total. It's more useful if you have a restricted date range if you have to go to the bound index, since it's organized by year.
Thanks to everyone. I found it, but I'm wondering whether this index is really an objective "quality seal" since I know a professor, who is highly cited, but getting his citations through a good network of connections with all groups in his field, so it's like a club, where people knowing each other make the citations grow...
It is "objective" only in the sense that it is just a statistics. However, one can read too much into it, and one can also read too little into it. Just be aware of what is being measured, how it is being measured, etc. You normally cannot evaluate anything using just ONE criteria (except for quackeries and their inability to get into any peer-reviewed journals).
Citations can be looked up here http://isiknowledge.com/
you need to access from an academic institution
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