If you don't know what to do, simply click the "Play" button and you'll see :)
(In terms of "Timeseries", if True, it will show year by year; if False, it will show the aggregated result (1990-2021).)
This visualization shows the citation flows based on fields of study. You can select the source and specify the time range.
Source code of this visualization: https://observablehq.com/@hongtaoh/sankey-diagram-of-citation-flows