Q. Can you recommend any citation data visualization tools?

Here's a good guide to several popular citation visualization tools: https://guides.library.harvard.edu/c.php?g=311134&p=4423814

And here's a web article about using Google Scholar for visualization of citations: https://people.cs.uct.ac.za/~mkuttel/VISProjects2015/VISSanbyTODDYANG/index.html

1. VOSviewer and CitNetExplorer are both from Leiden, with VOSviewer being preferred. Sci2 also has a good reputation.
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3. Paperscape is another citation visualization tool, available for arXiV papers.
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5. Please note that some of these tools (e.g. VOSviewer) work directly with Web of Science/Knowledge data, which is nice. You may want to explore Web of Science’s built-in Analyze Results and Citation Report features (available after you perform a search). There are built-in visualizations (treemaps and bar graphs), default metrics (e.g. average citations per item) and several ways to refine the search. This can be very useful in doing citation analysis for individuals or groups.