As a plugin developer you can use this plugin as dependency of your plugin by adding a dependency tag to your POM.
To add the latest version of this plugin as a maven dependency, use the following:
<dependency>
<groupId>org.jenkins-ci.plugins</groupId>
<artifactId>disk-usage</artifactId>
<version>573.v5269a_8d16a_db_</version>
</dependency>