dart – API JSON in aqueduct doubt

Good morning people
I have created an API in aqueduct initially
In it I created a series model class and inside it has information about Author , year, idserie , blz there wanted to create a model class episodes she would have |iddoepsodium ,episodes, idserie(here and foreign key of the series table)
How can I do to relate the episodes with the series as I can do?
I request guidance because I have never made an API

class series extends ManagedObject<_Serie> implements _Serie {
String get detail => & # $ idserie by $ author & # 39 ;;
}

`class _Serie {
@PrimaryKey
Int Idserie;

@Culumn ()
String author;

@Column ()
Int year;}
`