Journal articles provide focused, reliable, and often up-to-date, information and analysis on public issues. Many of these journals use the peer review process, so that submitted work is vetted by scholars in the field and is improved by the author before it is published. The following indexes are the most relevant for finding scholarly journal articles in the field of political science.
Topics can frequently deal with issues beyond the scope of political science. In those cases, use a subject-specific index like the ones below to find pertinent articles with research and analysis in areas including economics, education, law, and sociology.
Usually researchers find more sources by looking at the footnotes in an article or book, but these will always be older than the publication you have in hand. Citation indexes like the Web of Science (which includes sections for the Social Sciences, Arts and Humanities, and Science) are set up to search for sources cited in the footnotes of journal articles as soon as they become available.
This allows you to find newer articles which cite the books and articles you already know are key for your topic. By relying on connections between authors rather than subject words and by moving forward in time, citation searching can open up new avenues of research.
See this tutorial for more information on cited reference searching.