"A third-order class in Wikidata, e.g., vehicle model series (Q29048319) or second-order class (Q24017414), is a class all of whose instances are implicitly or explicitly instances of (P31) second-order class (Q24017414). A class is implicitly a third-order classes if it is a subclass of (P279) another class that is a third-order class. These implicit instance of (P31) statements are not all observable in Wikidata.There are very few natural third-order classes. Before stating that a class is instance of (P31) third-order class (Q24017465) check that it is actually a third-order class."@en