No SYSTEM identifier declared for external data-entity's notation.

#6025 Run-time catchable error

No SYSTEM identifier declared for external data-entity's notation.

Additional Information

For notation 'A':
    or
For external entity 'X': for notation 'Y'.
    or
For element 'X': for element attribute 'Y' = entity "Z": for notation 'W'
    where Z is the name of the attribute's external data-entity.
    or
For element 'X': for element attribute 'Y' = notation "Z":

Explanation

An external entity's notation does not have a specified system identifier.