A reference to a group is created as a child of an element, group or complex type, and makes the referenced group available to its parent.
You can create a referencing group in any of the following ways:
Select the Group tool in the Toolbox, and click on an element, group, or complex type symbol.
On the Items tab of the property sheet of a group particle, click the Add Reference to Group tool (see Group Particle Properties).
For general information about creating objects, see Core Features Guide > Modeling with PowerDesigner > Objects.