How are the carpels and ovaries typically structured in Gentianales flowers?

In the Gentianales order, the carpels are generally united to form a compound ovary. While this fusion is characteristic of the order, it is notable that in the Apocynaceae family, these carpels typically become separated secondarily.1

Regarding the position of the ovary within the flower, it is generally superior. A significant exception exists within the Rubiaceae family, where the ovaries are mostly inferior. Additionally, the ovules within these ovaries possess a single integument, and the nucellus is one-layered.1