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DSpace Addon "Modules" are explicitly [ Maven Artifacts| Module Projects that are "part of" the DSpace distribution process or can be added to your DSpace instance to enhance its functionality. DSpace Addon Modules may have an SVN location, but generally are distributed as MAven Maven Artifacts View via the Maven Central Repository, thus you can add them to your DSpace installation as dependencies rather than patching your source to add functionality.
References concerning Maven Artifact and MultiModule Projects
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