The <apipackage> element is a reference to a package.
This element can be used to reference a package from another DITA topic type.
<task id="httpxml"> <title>Getting an XML file through an HTTP connection</title> <taskbody> <steps> <step><cm>Open the connection.</cm> <info>You use <apipackage keyref="com.ibm.xtools.patterns.framework.uml2">com.ibm.xtools.patterns.framework.uml2</apipackage> in a Java application.</info> </step> ... </steps> </taskbody> </task>