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ProjectIsReferencedOnDocument
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.. rubric:: Description


This modelling pattern allows to express that a project is
referred to on a document.
No information about the type of reference is made - it could be symbolic,
textual or both.
It is assumed that, while parsing the information about the COAC from a 
data file, an entity for the underlying document can be found or is created
in a database that contains information about documents.


.. rubric:: Definition


A project (x1) is referenced on a document (x2).


::

    
    ProjectIsReferencedOnDocument(x1, x2) <->
        Activity(x1) &
        ClassOfInformationObject(x2) &
        MMT:ReferenceToIndividualOnDocument(x1, x2) .
    

.. rubric:: Roles

1. hasProject

2. hasOnDocument

.. rubric:: Restrictions

* Role filler of hasProject must have entity type Activity.

* Role filler of hasOnDocument must have entity type ClassOfInformationObject.

* One of:

  * Role filler of hasProject must be classified as Project.

  * Role filler of hasProject must be used as the role filler of hasThis with respect to the :doc:`../ThisIsAProject/index` pattern.

* One of:

  * Role filler of hasOnDocument must be a specialization of Document.

  * Role filler of hasOnDocument must be used as the role filler of hasThis with respect to the :doc:`../ThisIsADocument/index` pattern.