In the DG, the description directly under the model class diagram talks about ObservableList<Person>, yet it is not on the diagram.
Either the description needs to be accompanied with another diagram and placed in another section or the description should be removed entirely.

In the DG, the description directly under the model class diagram talks about
ObservableList<Person>, yet it is not on the diagram.Either the description needs to be accompanied with another diagram and placed in another section or the description should be removed entirely.