public class Entity
{
	public int Id {get; set;}
}


public class Employee: Entity
{
	public string Name {get; set;}
}

public class BaseDivision: Entity
{
	public string Name {get; set;}
        public IList<Employee> Employees{get; set;}
        public BaseDivision Parent {get; set;}
}

public class Division1: BaseDivision
{
	public Division2 Division2{get; set;}
        public Division3 Division3{get; set;}
}