Hi,

please have a look here:

Basics of relations

Note the following particularities when using relations:

• A software unit cannot create a relation with itself.
• A relation can only be created in one direction at a time. This means that a software unit cannot create a relation to another software unit if a relation back from it already exists.

  Example: Software Unit A has a relation with Software Unit B. Software Unit B cannot establish an additional relation with Software Unit A and can also not access the program elements of Software Unit A.

• Relations that would lead to circular references cannot be created.

regards

sancruz