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Download JUnit Tutorial (PDF Version)1 - JUnit Quick Reference Guide
A quick JUnit reference guide for Java Programmers.
2 - JUnit Useful Resources
A collection of JUnit Sites, Books and Articles is given at this page.
3 - Java Tutorials
If you are starting with Java then it's best place to start with.
4 - JUnit Tutorial in PDF
Download a quick JUnit tutorial in PDF format.