To avoid confusion, this article (and the accompanying specialization) uses the subject label for the same thing as the SKOS concept, and uses the concept label in the DITA sense.

You can model these constraints, conditions, and invariants independently using DITA specialization, probably by extending the concept topic type.

The concept of teacher specialization has gone through four stages since it took shape, and professional teacher training in the international teacher education system has varied across six models.