Multiple unique level 3 classifications are being used within the article group
Error:
Multiple unique level 3 classifications are being used within the article group.
Explanation:
An article group is classified in its entirety in the same classification layer. It is therefore not possible to classify an article from the same group in a different classification level. This is a classification at different places in the third layer of the classification.
Solution:
Determine how this group should be classified and classify the whole group in the same classification.
