RSA: Broken references in UML class

Hello,

I am working with IBM Rational Software Architect 9.1.2 and I am currently facing some troubles. If I validate an UML class it shows lots of errors related to broken references like the following:

Description    Resource    Path    Location    Type
The feature 'general' of 'AACatalogs::com.aa.nextgen.catalogs.dao::CatalogDAO::<Generalization>' has a reference to 'AAPersistence::com.aa.nextgen.persistence::NGCoreDAO' which cannot be found.    AACatalogs.emx    /GrupoEKTArchitecture    AACatalogs::com.aa.nextgen.catalogs.dao::CatalogDAO::<Generalization>    Model Validation Problem

The question is, how can I manually repair that broken reference?

Thanks in advance,
Francisco R.